While many cast French Onion Soup as fine dining restaurant fare, it really is easy enough to make this soup at home. Read on for my recipe, hints, and tips for making this Classic French Onion Soup in your own kitchen. Yes, you really can make fine restaurant-quality food at home and your kitchen will have the intoxicating aroma of a French bistro!

The main ingredient you will need for this soup is …. patience! You can’t buy it at the supermarket but you will need it as, full disclosure, this is not a quick soup to make. It is not a particularly difficult soup to make but there are steps and time involved. However, your reward will be a tasty comfort food, worthy of being on the menu of a fine restaurant! The bonus, of course, is that you will have the sense of achievement for having made a time-honored classic French soup right in your very own kitchen.

The main flavor of this old classic is that of caramelized onions and that is what takes the time and patience. Be prepared to spend anywhere from 45 minutes to an hour or more to caramelize the onions and don’t skip this step or try to shorten up, or hasten, the process by increasing the heat during the caramelization process. This slow cook process is what will give the supreme flavor base to an exceptionally good French Onion Soup.

It’s hard to imagine such a flavorful broth-based soup coming from such humble and plain, almost non-descript ingredients. Onions, stock (beef or chicken or a combination of both), wine, some garlic, thyme, Worcestershire sauce, and some quality melting cheese are the basic ingredients needed.

Choosing and Preparing the Onions

There are any number of schools of thought on the “best” variety of onions to use for French Onion Soup. I simply use large yellow onions in my recipe. You can, of course, use other varieties of onions but the more economical basic yellow onions will make a fine flavorful soup. Large onions are needed for this soup because you will want long strands of onion in the soup. Small onions won’t give you that and they will cook up during the caramelization process into, well, nothing discernable.

This soup recipe requires 2¼ pounds of large yellow onions. Start by cutting off and discarding the stem and root ends from each onion then cutting the onions in half, vertically, from stem to root end (i.e., pole to pole). Peel the onion halves. I recommend using a mandolin to cut the onions into uniform size. I do not recommend slicing the onions too thinly because they will burn and/or shrivel up into nothing. I find a good general guide is to cut the onions into approximately ¼” width pieces. Slice the onion halves vertically, from pole to pole, to get long onion strands. If you don’t have a mandolin you can, of course, cut the onions using a very sharp knife. Lay the onion halves, cut side down, and slice into long strips, according to the grain of the onion, each approximately ¼“ wide.

Choosing the Pan

There is a lot of raw onion to begin with and we want all the pieces to be caramelized so I recommend, first of all, choosing a very heavy bottomed cooking vessel as there will be less chance of the onions burning in it than if a lightweight pan is used. I recommend using a large, wide sauté pan that is not too deep as it will give sufficient room for all the onions to be spread out. If you have a wide-shaped 4 or 5-quart Dutch Oven that is stovetop safe to medium-high temperature, that is also an option. However, if you have, and plan to use, an enameled cast-iron Dutch Oven in this recipe, be sure to first check the instructions that came with it to confirm it can sustain being used over medium-high heat on the stovetop. As a last resort, a large stockpot could be used but its depth makes it more difficult to stir the onions as they caramelize.

Caramelizing the Onions

This is the most time-consuming task of making this soup and where there needs to be a hefty dose of the ingredient, patience! Caramelized onions are not the same as sautéed onions and the caramelization process takes time.

Begin by heating the olive oil in the pan over medium heat then add the butter. Once the butter has melted, add the onions. Stir the onions well to coat them all completely in the oil and butter. Spread the onions out as well as you can in the pan. Cover the pan for the first 3-4 minutes to allow the onions to soften. Stir the onions once or twice during this period. Watch for signs of the onions sticking to the pan or starting to burn which requires the heat to be reduced and more stirring.

Remove the pan cover and continue cooking the onions, uncovered, stirring about every 2-3 minutes for the first 15 minutes. It’s important for the onions to have contact with the pan in order to caramelize but it is just as important that the onions don’t burn. Pans heat differently and so does every stove. The heat levels indicated in my recipe should be used as a guide only. If the onions start to stick to the pan, add a wee bit of stock to loosen them but also consider lowering the temperature as necessary. I recommend erring on the side of caution and reducing the heat versus having burnt or scorched onions which would ruin the soup. So, know your stove and adjust the cooking temperature to get a good caramelization, even if the process may take a little longer. After the first 15 minutes, sprinkle some salt over the onions and start stirring the onions more frequently (i.e., every minute or so). After 20 minutes of cooking, sprinkle the onions with brown sugar and give them a good stir. Reduce heat to medium low and continue stirring onions frequently.

Be prepared to have patience for this process and don’t be tempted to increase the heat to hasten the process. There is no magic time for caramelizing onions. They are done when they are a deep caramel or chestnut brown color. That said, expect the whole caramelization process to take at least 45-60 minutes or longer. Once they reach the caramelized stage, add the minced garlic and stir continuously for 15-20 seconds, just until the garlic becomes fragrant. Do not let the garlic scorch. Roasted garlic can be used instead of minced garlic for a more subtle flavor, if desired.

Deglazing the Pan

When the onions have caramelized, you will notice brown bits on the bottom of the pan. These are known as “fond” and they carry fabulous flavor that you want to embed into the soup. To dislodge them from the pan, remove the hot pan from the heat and pour in the wine that is needed to deglaze the pan. Increase the heat to medium-high and immediately return the pan to the heat. Using a wooden spoon, scrape up all the brown bits of flavor and cook until the wine has reduced to less than half its original amount. This will cook off the alcohol in the wine and will not leave a heavy alcohol flavor. Either a dry red or white wine can be used. Red will give more depth of flavor and it is the one I use if I am using all or mostly beef stock in this recipe. By this time, the onions should have a jam-like consistency.

Using a Thickening Agent

I use 1 tablespoon of cornstarch in this soup. All-purpose flour can also be used; however, I find cornstarch will yield a clearer soup. The tablespoon of thickener will not make this a thick soup nor is that the objective. It will still be very brothy as is traditional for French Onion Soup. I find the thickener just adds a wee bit of body to the soup. However, if you prefer a totally thin brothy soup, simply leave out the thickener. If you do use a thickening agent, sprinkle it on the onions after the pan has been deglazed and stir for about 30 seconds.

Stock

The liquid ingredient in this soup is a good, flavorful stock. While beef stock is the traditional stock used in French Onion Soup, either beef or poultry stock can be used, or a combination of both. Some find using all beef stock is a bit strong on flavor while the poultry stock (either chicken or turkey) is milder in flavor. I like using a mixture of both beef and poultry stock for balance but that is purely a personal preference. Know that the better the quality of stock that is used, the more flavorful the soup. My preference, of course, is to use my own homemade stock. For my beef stock recipe, click here and for my turkey stock recipe, click here.

Seasoning

There is not a lot of seasoning added to this soup and it should not be needed if a good quality flavorful stock is used. A bay leaf and a couple of sprigs of fresh thyme are it for herbs. While I have listed Passata as an optional ingredient, I do like to add a couple of tablespoons as it deepens the flavor of the soup without taking it down another entirely different flavor profile or detracting from the caramelized onions. The small amount of Passata will not turn the soup into a tomato flavored dish. Two teaspoons of Worcestershire sauce deepen the flavor and contribute to the savouriness of the soup.

Once the stock and seasonings have been added, bring the soup just to the boiling point then reduce heat to low and simmer for approximately 35-40 minutes to let the flavors blend.

Baguette and Cheese Topping

Some claim the best part of French Onion Soup is the cheesy toast topping. While Gruyère is the traditional cheese used in this soup, other kinds of cheeses work well, too, so long as they are good melting cheeses. Havarti, Provolone, Swiss, and Mozzarella are among my favorites. I like to use a combination of cheeses and the soup in the photos that accompany this post contained shredded Gruyère, Havarti, Swiss, and finely grated Parmigiano Reggiano. For the cheeses that are shredded, use the side of a box grater that has the large holes. A very small hole grater or microplane will be needed for the Parmigiano Reggiano. If using more than one kind of shredded cheese, toss them together in a bowl to mix well. After I have added the shredded cheeses, I like to add a sprinkling of finely grated Parmigiano Reggiano to each bowl.

Slice a baguette into ½“ slices, either straight or diagonally cut. Depending on the width of the soup bowls and the size of the baguette slices, either one or two baguette slices per bowl will be required. There is no need to completely cover the entire soup with baguette slices. Lightly brush each baguette slice, both sides, with olive oil. Place slices on a baking sheet and toast in a preheated 400°F oven until light golden brown, turning the slices over once during the toasting process. Once the toasts come out of the oven, adjust the oven rack to within 6” – 8” from the broiler element.

You will need broiler-proof onion soup bowls for this recipe as they will need to be able to withstand the high heat of the broiler. Set the bowls on a rimmed baking sheet and ladle the hot soup into the bowls, leaving enough room at the top of each bowl for the baguette slice(s) and cheese. Place the toasted baguette slices on top of each soup serving and sprinkle generously with approximately ¼ cup of cheese (or a bit more!) per serving. The exact amount of cheese needed will depend on the size and width of the soup bowls as they come in different shapes, sizes, and styles.

Adjust oven to broiler mode. Place the baking sheet containing the soup bowls under the broiler and watch the soups closely. This process will not take long at all and can quickly go from a lovely melted cheese topping to burnt offerings in seconds! The soups are done when the cheese is melted and the soup is seen bubbling around the edges.

Making the Soup Ahead and Storing

This soup can be made ahead and, minus the toasts and cheese, will keep for up to 3 days in the refrigerator. It must, however, be reheated before being placed under the broiler as it will not be in the oven long enough for the soup itself to heat. In fact, I think this soup is better the second or third day as the flavors have had a chance to deepen. The soup base can also be frozen in an airtight freezer container for longer storage. Simply defrost when needed, heat the soup, and proceed with the directions for the toasted baguette and cheese topping.

Classic French Onion Soup

Ingredients:

2¼ lbs large yellow onions, cut in half vertically, peeled, and sliced into ¼“ slices
2+ tbsp olive oil
3+ tbsp butter
2 tsp brown sugar
3-4 garlic cloves, minced
1 tbsp cornstarch or flour (optional)
1/3 – ½ cup red or white wine
4 cups warm beef or poultry stock, or a combination of both
2 tbsp Passata (optional)
2 tsp Worcestershire sauce
1 large dried bay leaf
2 sprigs fresh thyme
Fine sea salt and fresh cracked pepper, to taste

Baguette, cut into ½“ slices (allow 1-2 slices per serving, depending on bowl width and size of baguette slices)
Olive Oil for brushing baguette slices
Apx. 1½ – 2 cups shredded melting cheese(s) of choice (e.g., Gruyère, Havarti, Swiss, Provolone, Mozzarella) (shredded on the large hole side of a box grater)
Finely grated Parmigiano Reggiano Cheese (optional)
Fresh thyme for garnish (optional)

Method:

[NOTE: Broiler-proof onion soup bowls are required for this recipe.]

Tie the bay leaf and sprigs of fresh thyme together with kitchen string to make a bouquet garni. Set aside.

Remove and discard the stem and root ends from the onions. Cut the onions in half, vertically, from pole to pole, and peel onions. If you have one, use a mandolin to cut the onion halves vertically into ¼“ slices. Alternatively, lay the “half-moon” onions, cut side down, on a cutting board and, using a sharp knife, slice vertical slices, according to the grain of the onion, about ¼ “wide.

Heat olive oil over medium heat in a large, wide, heavy-bottomed sauté pan or a wide 4 – 5-quart Dutch Oven that is stove-top safe to medium-high heat. Add the butter. Once the butter has melted, add the onions. Stir to coat the onions well with the oil and butter and spread the onions out in the pan. Cover pan for the first 3-4 minutes to allow the onions to soften. Stir once or twice during this time and, if the onions start to stick to the pan, reduce the heat to prevent them from burning.

Remove the cover from the pan or Dutch Oven and continue cooking the onions, uncovered, stirring occasionally, about every 2-3 minutes, for the first 15 minutes to prevent onions from sticking to pan. After about 15 minutes, sprinkle onions with some salt and start stirring more frequently (i.e., every minute or so). After 20 minutes of cooking, stir in the brown sugar. Reduce heat to medium-low and continue to stir the onions frequently as they begin to caramelize, scraping up any brown bits (the fond) from the bottom of the pan with each stir. If the onions start to show signs of burning or sticking to the pan, reduce the heat further as necessary and add a little bit of stock. Do not let the onions burn or scorch. Expect the whole caramelization process to take at least 45-60 minutes or longer until the onions are a deep caramel/chestnut brown color.

When the onions turn a deep caramel or chestnut brown color, add the minced garlic and stir continuously for about 15-20 seconds, until the garlic becomes fragrant but, at the same time, ensuring the garlic does not scorch.

Remove the pan from the heat and add the wine needed to deglaze the pan. With heat set to medium-high, immediately return the pan to the stove and, using a wooden spoon, scrape up the brown bits on the bottom of the pan. Cook until the brown bits have been loosened from the pan and the wine has reduced to less than half of its original amount and the mixture has a jam-like consistency.

If using thickener (either cornstarch or flour), sprinkle it over the onions and stir for about 30 seconds.

Add the stock, Passata, Worcestershire sauce, bay leaf, and thyme. Season with salt and pepper to taste. Bring mixture just barely to the boiling point then reduce the heat to low, partially cover (i.e., pan cover slightly askew), and simmer for about 35-40 minutes to let the flavors develop.

While the soup is simmering, position oven rack to center of oven and preheat oven to 400°F.

Lightly brush baguette slices on both sides with olive oil and place on a baking sheet. Place bread in preheated oven to toast until golden brown, turning slices over once to ensure both sides are toasted. Remove toasted baguette slices from oven and set aside. Adjust oven rack position to 6-8” inches from broiler element.

Place broiler-proof onion soup bowls on rimmed baking sheet. Remove bay leaf and thyme from the soup and ladle soup into bowls, leaving enough room on the top for the toasted baguette slice(s) and cheese. Place baguette slice (or slices, if two are required, side-by-side (not overlapping)) in each bowl. Top each bowl with a generous ¼ cup of shredded cheese of choice or a combination of favorite melting cheeses. If desired, add a sprinkle of finely grated Parmigiano Reggiano cheese to each bowl (or you can mix this cheese in with the shredded cheeses, if you wish).

Set oven to broil mode. Transfer soup-filled bowls to oven and broil just until cheese is melted and soup is bubbling at the edges of the bowls. Watch carefully as this will not take very long. It will go from a lovely gooey cheese topping to burnt offerings in mere seconds!

This soup (minus the toasts and cheese) will keep for up to 3 days in the refrigerator but must be heated before being placed under the broiler as it will not be in the oven long enough for the soup to heat. The soup base can also be frozen in an airtight freezer container for longer storage. Add the toasts and cheese at time of serving.

Yield: Apx. 4-6 servings

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Classic French Onion Soup

Perfectly caramelized onions, combined with a rich and lightly seasoned broth and a cheesy toast topping, are the recipe for a flavorful Classic French Onion Soup.

Course Soup

Cuisine French

Keyword broth-based soup, Classic French Onion Soup, French Onion Soup, soup,

Servings 4

My Island Bistro Kitchen My Island Bistro Kitchen

Ingredients

• 2¼ lbs large yellow onions, cut in half vertically, peeled, and sliced into ¼“ slices
• 2 + tbsp olive oil
• 3 + tbsp butter
• 2 tsp brown sugar
• 3-4 garlic cloves, minced
• 1 tbsp cornstarch or flour (optional)
• 1/3 – ½ cup red or white wine
• 4 cups warm beef or poultry stock, or a combination of both
• 2 tbsp Passata (optional)
• 2 tsp Worcestershire sauce
• 1 large dried bay leaf
• 2 sprigs fresh thyme
• Fine sea salt and fresh cracked pepper, to taste
• Baguette, cut into ½“ slices (allow 1-2 slices per serving, depending on bowl width and size of baguette slices)
• Olive Oil for brushing baguette slices
• Apx. 1½ - 2 cups shredded melting cheese(s) of choice (e.g., Gruyère, Havarti, Swiss, Provolone, Mozzarella) (shredded on the large hole side of a box grater)
• Finely grated Parmigiano Reggiano Cheese (optional)
• Fresh thyme for garnish (optional)

Instructions

1. [NOTE: Broiler-proof onion soup bowls are required for this recipe.]
2. Tie the bay leaf and sprigs of fresh thyme together with kitchen string to make a bouquet garni. Set aside.
3. Remove and discard the stem and root ends from the onions. Cut the onions in half, vertically, from pole to pole, and peel onions. If you have one, use a mandolin to cut the onion halves vertically into ¼“ slices. Alternatively, lay the “half-moon” onions, cut side down, on a cutting board and, using a sharp knife, slice vertical slices, according to the grain of the onion, about ¼ “wide.

4. Heat olive oil over medium heat in a large, wide, heavy-bottomed sauté pan or a wide 4 – 5-quart Dutch Oven that is stove-top safe to medium-high heat. Add the butter. Once the butter has melted, add the onions. Stir to coat the onions well with the oil and butter and spread the onions out in the pan. Cover pan for the first 3-4 minutes to allow the onions to soften. Stir once or twice during this time and, if the onions start to stick to the pan, reduce the heat to prevent them from burning.

5. Remove the cover from the pan or Dutch Oven and continue cooking the onions, uncovered, stirring occasionally, about every 2-3 minutes, for the first 15 minutes to prevent onions from sticking to pan. After about 15 minutes, sprinkle onions with some salt and start stirring more frequently (i.e., every minute or so). After 20 minutes of cooking, stir in the brown sugar. Reduce heat to medium-low and continue to stir the onions frequently as they begin to caramelize, scraping up any brown bits (the fond) from the bottom of the pan with each stir. If the onions start to show signs of burning or sticking to the pan, reduce the heat further as necessary and add a little bit of stock. Do not let the onions burn or scorch. Expect the whole caramelization process to take at least 45-60 minutes or longer until the onions are a deep caramel/chestnut brown color.

6. When the onions turn a deep caramel or chestnut brown color, add the minced garlic and stir continuously for about 15-20 seconds, until the garlic becomes fragrant but, at the same time, ensuring the garlic does not scorch.
7. Remove the pan from the heat and add the wine needed to deglaze the pan. With heat set to medium-high, immediately return the pan to the stove and, using a wooden spoon, scrape up the brown bits on the bottom of the pan. Cook until the brown bits have been loosened from the pan and the wine has reduced to less than half of its original amount and the mixture has a jam-like consistency.
8. If using thickener (either cornstarch or flour), sprinkle it over the onions and stir for about 30 seconds.
9. Add the stock, Passata, Worcestershire sauce, bay leaf, and thyme. Season with salt and pepper to taste. Bring mixture just barely to the boiling point then reduce the heat to low, partially cover (i.e., pan cover slightly askew), and simmer for about 35-40 minutes to let the flavors develop.
10. While the soup is simmering, position oven rack to center of oven and preheat oven to 400°F.
11. Lightly brush baguette slices on both sides with olive oil and place on a baking sheet. Place bread in preheated oven to toast until golden brown, turning slices over once to ensure both sides are toasted. Remove toasted baguette slices from oven and set aside. Adjust oven rack position to 6-8” inches from broiler element.

12. Place broiler-proof onion soup bowls on rimmed baking sheet. Remove bay leaf and thyme from the soup and ladle soup into bowls, leaving enough room on the top for the toasted baguette slice(s) and cheese. Place baguette slice (or slices, if two are required, side-by-side (not overlapping)) in each bowl. Top each bowl with a generous ¼ cup of shredded cheese of choice or a combination of favorite melting cheeses. If desired, add a sprinkle of finely grated Parmigiano Reggiano cheese to each bowl (or you can mix this cheese in with the shredded cheeses, if you wish).

13. Set oven to broil mode. Transfer soup-filled bowls to oven and broil just until cheese is melted and soup is bubbling at the edges of the bowls. Watch carefully as this will not take very long. It will go from a lovely gooey cheese topping to burnt offerings in mere seconds!
14. This soup (minus the toasts and cheese) will keep for up to 3 days in the refrigerator but must be heated before being placed under the broiler as it will not be in the oven long enough for the soup to heat. The soup base can also be frozen in an airtight freezer container for longer storage. Add the toasts and cheese at time of serving.

Recipe Notes

[NOTE: Broiler-proof onion soup bowls are required for this recipe.]

Yield: Apx. 4-6 servinggs

 

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