Mix the vinegar and soda in a small container and add to cake mixture next to last.
Mix the red cake color, cocoa, and vanilla in another small container and add to cake last.
Combine sugar, buttermilk, butter, cake flour, eggs, salt, and baking powder. Mix all ingredients and add others as directed.
Bake at 350°F for 30-35 minutes.
For topping: Mix flour and milk, cook to thicken, and let cool. Do not refrigerate.
Cream butter, sugar, and Crisco, and add cool mixture. Do not over beat.