1 yellow cake mix
8 oz. sour cream
4 eggs
1 c. oil
1 tsp. vanilla
1 c. brown sugar
1 tbsp. cinnamon
1 c. powdered sugar
4 tbsp. hot water
1 tbsp. vanilla

Mix together cake mix, sour cream, eggs, oil and vanilla. Pour 1/2 of batter in sheet cake pan. Mix brown sugar and cinnamon. Sprinkle over batter in pan and pour rest of batter on top. Bake at 350 degrees until done. While cake is still warm, mix powdered sugar, water and vanilla; pour over warm cake.