Buttermilk Brownies

My Grandma Marie's recipe. I remember having these at holiday get-togethers. I would practically stand by them at the dessert table & eat as many as I could! Maybe that's why I have a weight problem. LOL

2 C. sugar
2 C. flour
3-4 T. cocoa powder
1 C water
1/2 c. margarine
1 C. oil
1/2 c. buttermilk
2 eggs
1 t. baking soda

Cake:
Preheat oven to 350 degrees. Sift flour, sugar & cocoa into large bowl. In saucepan, bring to a boil-water, oil & margarine. Pour over dry ingredients & beat until creamy. Add buttermilk, eggs & baking soda. Beat thor oughly. Bake in greased jelly roll pan for 20 min.

Frosting:
1/3 c. buttermilk
1/2 c. margarine
1/4 c. cocoa powder
3 c. powdered sugar
1 t. vanilla
2 c. mini marshmallows
Bring to a boil the buttermilk, margarine & cocoa. Add powdered sugar & vanilla. Beat well. Add marshmallows. Spread over warm brownies. Yummy!