Streusel Topping (below)
3 med. sized apples
Sugar
1 c. soft butter
1 (16 oz.) container sour cream
2 1/2 c. flour
1 tbsp. baking powder
2 tsp. baking soda
2 tsp. vanilla
4 lg. eggs

Prepare Streusel Topping; set aside. Peel, core, and thinly slice apples. In bowl, toss apples with 2 tablespoons sugar. Grease 14 x 10 inch roasting pan. Preheat oven to 350 degrees. In large bowl, with mixer at medium speed, beat butter with 1 1/2 cups sugar until light and fluffy. Add sour cream and remaining ingredients; beat at low speed until blended, constantly scraping bowl. At medium speed, beat 1 minute. Spread batter in pan; arrange apple slices on top. Sprinkle with Streusel Topping. Bake 45 to 50 minutes until cake pulls away from sides of pan. Cool in pan on wire rack 10 minutes. Makes 18 servings.

Streusel Topping: In bowl, knead 1 cup walnuts (chopped), 2/3 cup flour, 1/4 cup packed brown sugar, 4 tablespoons butter, and 1 teaspoon cinnamon into large pieces.