1 box yellow cake mix
1/2 cup oil
12 oz sour cream
1 small box vanilla instant pudding
1/4 cup sugar
1-1/2 tsp cinnamon
Mix all ingredients except sugar and cinnamon together. Pour half into a greased bundt pan. Mix sugar and cinnamon together.
Sprinkle over batter and then cut through with a knife to swirl. Add rest of batter. Bake at 325 degrees for 1 hour. Cool 25 minutes, then remove from pan.