PREPARATION:
Preheat your oven to the temperature indicated on the yellow cake mix package. Grease 9×13 baking dish.
In a large mixing bowl, combine the yellow cake mix, oil, eggs, and sour cream. Mix well until all the ingredients are well combined.
Put half the batter into baking dish.
Mix together ground cinnamon and brown sugar and sprinkle over entire cake. Pour over rest of batter.
Place the pan in the preheated oven and bake according to the instructions on the yellow cake mix package or until a toothpick inserted into the center comes out clean.
To the instructions