I can't remember where I saw this recipe, but it is fabulous!!!! Next time, I may tweak the amount of sugar and oil. Whoa, the recipe calls for a ton of both.
1 Yellow Cake Mix
3/4 Cup of Oil
1 Cup of Sour Cream
1 Cup of Brown Sugar
1 Tablespoon of Cinnamon
2 cups of Powdered Sugar
1 Tablespoon of vanilla
4 Tablespoons of Milk
Pre-heat oven to 325 degrees
Mix cake mix, eggs, oil and sour cream in a bowl. Spray 9 x 11 cake pan with non-stick spray (I use Bakers). Spread HALF of the cake mix into the pan.
Mix brown sugar and cinnamon very well. Spread over the cake mix.
Carefully pour the rest of the cake mix. With a knife, swirl through the cake to spread the sugar/cinnamon mix throughout the cake. Very similar to how you would make a marble cake.
Bake for 40 minutes or until toothpick comes out clean.
Remove from oven, spread frosting over cake and let sit for 15 minutes. No cheating!