1 1/2 c. white flour
1 c. whole wheat flour
3/4 c. sugar
1 c. brown sugar
3/4 c. butter
1 tbsp. cinnamon
1 c. buttermilk
1 tsp. baking soda
1 egg
1/2 tsp. baking soda

Mix first 6 ingredients completely. Set aside half of this mixture for topping. Add last 4 ingredients to the rest of the first mixture and beat for 4 minutes with mixer. Pour batter into greased and floured 9"x12" cake pan. Top with crumb mixture and bake at 350 degrees for 45 to 50 minutes.