Pina Colada Dessert Squares

Layer 1:
2 cups all-purpose flour
2 teaspoons baking powder
1/2 teaspoon salt
1/2 cup (1 stick) margarine
2 egg yolks, mixed with 1/2 cup milk

Layer 2:
4 tablespoons cornstarch
2 cans crushed pineapple (with juice)
2 teaspoons lemon juice
2 teaspoons vanilla extract

Layer 3:
2 egg whites, beaten
1/2 teaspoon cream of tartar
2 tablespoon Sweet 'N Low
1 cup coconut

Mix all ingredients in layer 1 together and press into a greased 9 x 13-inch pan; set aside.

Cook ingredients in layer 2 together until thick and glossy. Place the pineapple mixture over the crumb mixture (layer 1).

Whip egg whites in layer 3 until very stiff with cream of tartar. Add remaining ingredients. Spread this mixture very gently over the pineapple layer. Bake in a preheated 350 degree F oven for 1 hour or until lightly browned.

Cut into squares.