CRUMB MIXTURE:

2 sticks butter, melted
2 c. flour
2/3 c. sugar
1 1/2 tsp. cinnamon
1 1/2 tsp. vanilla

Mix above in bowl until blended and crumbly; set aside.

BASE:

1 box Duncan Hines Butter Recipe cake mix
1 stick butter, melted
2/3 c. water
3 eggs

Blend base ingredients with electric beater. Grease and flour pan (12 x 17 or 10 x 15 - 9 x 13 1/2 may also be used). Bake at 375 degrees for 17 minutes or until batter will hold crumbs. Remove from oven and sprinkle with the crumbs. Place in over for an additional 17 minutes. Remove from oven; cool, then sprinkle with powdered sugar.