Combine eggs, sugar, flour, salt and lemon juice, mix well. Stir in the sour cream. Place apples in pastry shell, pour sour cream mixture over apples. Sprinkle with Crumble Topping. Bake in a preheated 400ºF. oven 35 to 40 minutes.

Crumble Topping:
1/4 cup of all purpose flour
1/4 cup of firmly packed brown sugar
1/4 cup of chopped walnuts
1/2 teaspoon of cinnamon
1/8 teaspoon of salt
3 tablespoons of butter

Combine the flour, sugar, walnuts, cinnamon and salt, cut in butter until mixture resembles coarse crumbs.