Ingredients:

Coffee Cake Topping
3/4 cup all-purpose flour
1/2 cup packed brown sugar
4 tbsp. butter
1/2 tsp. ground cinnamon

Apple coffee cake ingredients
1 boxed pound cake mix 16 oz.
8 oz. sour cream
2 medium eggs
1 tsp. vanilla extract
2 large Granny Smith apples (peeled, thinly sliced)

Preparation

In mixing bowl combine topping ingredients and mix until coarse crumbs result.
Chill topping, preheat oven to 350 F and grease 13″x9″ baking pan. In a large bowl, combine cake mix with eggs, vanilla and sour cream, mix about 1 min. until smooth.
Spread batter in cake pan and top with apple slices. Sprinkle topping over apples and bake for 45 to 50 minutes. Test to see if toothpick comes out clean. Cool on wire rack.