Chocolate Sheet Cake

Ingredients

• 1 stick butter
• 1/2 c. oil
• 1 c. water
• 1/2 tsp. salt
• 4 Tbsp. cocoa
• 2 c. sugar
• 2 c. flour
• 1/2 c. buttermilk
• 2 eggs, beaten
• 1 tsp. baking soda
• 1 tsp. vanilla
• 1 stick oleo
• 4 Tbsp. cocoa
• 6 Tbsp. milk
• 1 box powdered sugar
• 1 tsp. vanilla
• 2/3 c. chopped nuts