Cinnamon Roll Cake

It's 7 a.m. on a Monday morning. This is not by any stretch the most normal time for a new post, but I'm also studying new testament archaeology for an 11 a.m. exam and my brain needed a little break. This recipe is super easy and absolutely delicious.  True to its name, it tastes just like a cinnamon roll in cake form. You can't go wrong with a cinnamon roll period and in cake form it's arguably even better. I felt the same way when I made peanut butter and banana cupcakes. I made this recipe last week on my birthday and coincidentally my roommate has a coffee cake recipe that is almost exactly like this that she made for me the same day. Her recipe has a packet of vanilla pudding in it as well that makes it extremely moist (a.k.a. delicious). I'll find out the recipe and post that one later. I consider this to be more cake tasting than coffee cake tasting, but you'll never see me complaining about eating desserts for breakfast!
I don't know why I didn't find out the trick to add sour cream to box cake mixes a long time ago. It really is heavenly. Although the box mix makes it not quite as homemade, there are some days when a homemade cake isn't practical time-wise. So voila, I give you the perfect solution!
I got this recipe from The Repressed Pastry Chef, but she originally got it from Baseball, Baking and Books.

Cinnamon Roll Cake
Recipe from Baseball, Baking and Books
Yellow Cake Mix
4 eggs
¾ cup oil
1 cup sour cream
Mix by hand and pour in 13 x 9 greased baking pan.
1 cup brown sugar
1 tbsp cinnamon
Mix and pour over cake batter. Swirl into batter with knife.

Bake @ 325 for 30-40 minutes until done. Let cake cool 10 – 15 minutes before icing.
Icing: 2 cups powdered sugar
4 tbsp milk
Pour over warm cake