German Apple Cake

Why I Love This Recipe
While shopping at Costco, a free cookbook was offered. Of course, I had to have it. "In The Kitchen The Costco Way" is full of wonderful looking recipes. I changed this one ever so slightly because I used butter instead of shortening and buttermilk instead of milk and vinegar (sour milk = 1 cup milk+1 Tbsp. vinegar). It would be nice served with a dollop of whipped cream on top.
Ingredients You'll Need
2 1/4 cups all-purpose flour
2 large eggs
1/2 cup brown sugar
1 cup white sugar
1/4 tsp. salt
2 tsp. baking soda
2 tsp. ground cinnamon
1/2 cup butter, softened
1 cup buttermilk
2 cups peeled and thinly sliced Granny Smith Apples
Topping:
1/4 cup brown sugar
1/4 cup white sugar
1/2 tsp. ground cinnamon
1/2 cup chopped nuts
Directions
Preheat your oven to 350degrees F. Grease a 12 x 9-inch baking pan.
Combine the flour, eggs, brown sugar, white sugar, salt, baking soda, cinnamon, butter and buttermilk in a large mixing bowl using an electric beater on low speed. Mix until well blended.
Fold in the apples and pour into prepared baking pan.
Prepare the topping by mixing all the topping ingredients. Sprinkle over the top of the cake batter.
Bake in preheated oven 45 minutes or until a toothpick inserted in the center comes out clean.