Whisk 2½ tbsp cornstarch into the reserved ½ cup of poultry stock until somewhat smooth. Add 2-3 tablespoons hot mixture from the stockpot to temper the cornstarch mixture then add the thickener into the stockpot, stirring until mixture starts to thicken.
Transfer approximately 3 cups of the mixture to a blender and purée until somewhat smooth. Don't over-purée the mixture as it can become very watery and more difficult to thicken. Pour puréed mixture back into the stock pot. Stir to combine with remainder of unpuréed chowder mixture.
Yield: Apx. 6-8 servings
NOTE: The actual amount of thickener needed to achieve the desired thickness of the chowder depends on several factors, including personal preference. The quality and age of the corn and amount of moisture in it and how finely puréed a portion of the chowder is can also affect the thickness of the chowder. Don't over-purée the mixture as it will become very watery and harder to thicken. It is recommended that the amount of cornstarch called for in the recipe first be used and then more added if and as desired. Be sure to mix the cornstarch with a little water or stock and then temper it with a couple of tablespoons of the hot chowder mixture before adding and stirring it into the chowder. Go slowly with small amount of thickener at a time as it can set up fairly quickly.