1 cup sour cream
3/4 cup sugar
2 tablespoons flour
1/4 teaspoon salt
1 teaspoon vanilla
1 egg, beaten
3 to 4 cups diced apples
Topping:
1/2 cup brown sugar
1/4 cup butter
1/3 cup flour
1/4 cup nuts, if desired
Preheat oven to 400 degrees. In a large bowl combine first 6 ingredients and beat well. Add apples and mix well. Pour the mixture in an unbaked pie shell and bake at for 25 minutes.
Meanwhile, make topping: Combine brown sugar, butter, flour, and nuts mix well. Remove pie from oven and reduce heat to 250 degrees. Sprinkle topping on pie, then return to oven and bake for an additional 25 minutes.