1 Duncan Hines yellow cake mix
1 (8 oz.) sour cream
3/4 c. oil
4 eggs
1 c. brown sugar
3 tsp. cinnamon

ICING:

2 c. confectioners sugar
3 tbsp. milk
1 tsp. vanilla

Mix first 4 ingredients; beat according to mix. Pour into greased and floured 13x9-inch pan. Mix sugar and cinnamon; crumble over top of cake. Take large fork and swirl into cake. Bake according to directions on box. Mix icing and pour over hot cake.