Crazy Crust Pie

1 cup all-purpose flour
1 teaspoon baking powder
1/2 teaspoon salt
1 tablespoon granulated sugar
1 egg
2/3 cup shortening
3/4 cup water
1 can favorite pie filling
1 tablespoon lemon juice (optional)

Mix all ingredients together except apple pie filling, in a small bowl. Pour into a pie dish. Pour pie filling over flour mixture, but do not stir. Bake at 450 degrees F for 45 to 50 minutes.