Preheat oven to 350 F. Mix all cake ingredients. In a separate bowl mix up the topping and cut in the butter. Grease a 9x13 pan and put in 1/2 the cake batter and sprinkle with 1/2 the topping. Repeat by adding another layer with the remaining batter and sprinkle with the remaining topping. Bake for 40 minutes. Allow to cool 5-10 minutes before serving.