2 c. flour
1/2 c. sugar
1/2 tsp. baking powder
1/2 tsp. salt
1 c. butter
2 egg yolks, beaten

Combine flour, sugar, baking powder and salt; cut in butter as for pie crust. Mix in egg yolks (mixture will be crumbly). Press half of the mixture in bottom of 13 x 9 x 2 inch pan. Set remaining half of the mixture aside.

FILLING:

4 c. pared, cored and sliced apple (1/8 inch thick)
1/2 c. sugar
1/4 c. flour
1 tsp. cinnamon
1/4 tsp. nutmeg
2 egg whites, slightly beaten

Combine all of filling ingredients EXCEPT EGG WHITES; arrange over bottom crust. Crumble remaining crust mixture over filling. Brush egg whites over all. Bake at 350 degrees for 35-40 minutes. Cool. Drizzle with thin confectioners' sugar glaze if desired.