Preheat oven 350.
Grease 9x13 pan with butter/flour-I used a cast iron pan.
Beat butter and sugar.
Add eggs one at a time.
Add sour cream and vanilla.
Add dry ingredients, not over mixing.
Spread into pan and bake 15 mins. Then top with all of the crumbs and bake an additional 25 mins. Let cool and top with powdered sugar.