Preheat oven to 350 degrees. Prepare crust as follows: mix 2 cups flour, 1/2 cup sugar, salt and baking powder in a medium bowl. Cut in butter with a pastry blender. Gently mix in beaten egg.
Spray a 9" x 13" baking dish with non-stick cooking spray. Pat about 2/3 of the crumb mixture into the bottom of the dish.
Prepare apple filling as follows: cut peeled apples into thin, 1/2" slices. In a medium bowl, combine 1/2 cup sugar, 1/4 cup flour, cinnamon and nutmeg. Toss with apples. Spread apples onto prepared crust. Sprinkle reserved crust mixture evenly over apples and bake 40 minutes. When finished, allow to cool completely.
Prepare glaze as follows: mix together powdered sugar, half and half and almond extract. Put in a plastic sandwich bag and cut off a tiny portion of one corner of the bag. Drizzle glaze over pastry and allow glaze to harden before cutting into bars. Enjoy!