• Preheat oven to 350ºF.
• Mix the last 4 ingredients together to form the streusel mixture. (Sugar, cinnamon, cocoa and walnuts)
• Combine the dry cake ingredients and mix until well blended.
• Cream together the butter and sugar until light and fluffy. Add the eggs and sour cream, then add the dry ingredient mixture.

To Bake in a Bundt Pan:

• Place about 1/3 of the cake mix in a greased tube or bundt pan. Layer 1/2 of the streusel over the cake batter. Add another layer of each and end with a layer of cake batter. Bake for 50-60 minutes or until a toothpick inserted into the center of the cake comes out clean.

To Bake in a Loaf Pan:

• Add half of the batter to a large loaf pan. Then layer 1/2 of the streusel mix over the batter. Add the rest of the batter and top the cake with the other 1/2 of the streusel. This recipe will make one large loaf pan or two smaller ones. Bake as directed above.

To Bake in a 13"x9" pan:

• Add half of the batter to a large loaf pan. Then layer 1/2 of the streusel mix over the batter. Add the rest of the batter and top the cake with the other 1/2 of the streusel. Bake at 350ºF, but only for 25 minutes or so. Check carefully to see if it's baked after about 20 minutes.