Apple Pie a la Mode

1 egg
1 cup (1/2 pint) dairy sour cream at room temperature
3/4 cup sugar
2 tbs flour
1/4 tsp vanilla
dash salt
2 1/4 cups finely chopped, peeled cooking apples (about 2 - 3 apples)
1/4 tsp grated fresh lemon peel (or less if dried)
1 unbaked pie shell
crumb topping

Preheat oven to 450F (232C). Beat egg in a large bowl; blend in sour cream, sugar, flour, vanilla and salt. Fold in apples and lemon peel.
Pour into pie shell and bake 10 minutes. Reduce oven temperature to 350F (177C) and bake 30 minutes longer or until crust is golden brown.
While pie is baking, prepare Crumb Topping. Sprinkle topping over pie and bake 15 minutes longer. Serve warm or cool.

Crumb Topping:
1/4 cup (1/2 stick) butter at room temperature
1/2 cup sugar
1/3 cup flour
3/4 tsp cinnamon

Cut butter into sugar, flour and cinnamon; an electric mixer can be used.