1. Line 9”x9” baking pan with parchment paper, leaving enough paper overhang on sides to grip and lift baked square from pan for icing and cutting. Position oven rack in center of oven and preheat oven to 350°F.

For Shortbread Crust Base:

1. In bowl of stand mixer fitted with paddle attachment, mix flour and sugar together. With mixer set at medium speed, mix in the butter just until crumbly. A food processor may, alternatively, be used to make the base, pulsing the mixture for just a very few short bursts. Mixture will appear dry.
2. Press mixture evenly into prepared pan. Prick base all over with tines of fork to allow steam to release as the base bakes and to eliminate air pockets from forming. As the base mixture will be dry, this is easiest done if the ends of the fork tines are held between the index and middle fingers placed on the crust base as the fork is inserted and removed. This will help keep the base intact while it is being docked with the fork tines.
3. Bake 10-13 minutes, or just until edges of crust start to turn very pale golden in color and slightly pull away from pan sides. Do not overbake or crust will be hard. Cool for about 35-40 minutes in pan on wire cooling rack before adding topping.

For Topping:

1. Mix flour, baking powder, and salt together in small bowl. Set aside.
2. In bowl of stand mixer fitted with paddle attachment, beat the eggs lightly at medium-low speed. Increase speed slightly and beat in brown sugar and add the vanilla. Add the flour, baking powder, and salt, mixing just until combined and smooth. Remove bowl from mixer stand and manually fold in the pecans and coconut just until ingredients are combined. Pour mixture evenly over baked and cooled shortbread crust base. Bake in center of 350°F oven for about 25 minutes, or just until top is set and slightly firm to the touch. Cool completely in pan before icing.

For icing:

1. Place butter in bowl of stand mixer and beat at medium speed until creamy. Blend in the almond and vanilla extracts. Reduce mixer speed to low and gradually add the sifted icing sugar, about one-half cup at a time. Add the water (or milk), a couple of teaspoons at a time. Increase speed to medium-low to blend ingredients then increase speed to high and beat an additional minute to ensure ingredients are well combined and icing is smooth. Additional milk or water may be required to make icing of desired spreading consistency. If adding additional milk or water, add by ½ teaspoon at a time. Icing should be of spreading consistency but not “soupy”.
2. Using the parchment paper overhang, lift square from pan and transfer to cutting board. Peel away the parchment paper. Spread icing evenly over cooled square. Refrigerate for about 35-45 minutes to set icing before cutting squares into desired size. Squares freeze well.