Preheat oven to 325 F. Line a cupcake pan with cupcake liners. Set aside
To make the cupcakes, in a large bowl whisk together flour, cocoa powder, baking soda, salt and baking powder. Set aside.
In separate large bowl, cream together the sugar, butter and oil.
Mix in the egg, egg yolk, vinegar, vanilla extract, buttermilk and food coloring until well combined.
Combine the dry ingredients into the wet ingredients until well combined.
Fill cupcake liners 3/4 full of batter. (Be careful not to overfill) Shake and tap the pan on a hard surface to even out the batter and release any trapped air.
Bake for 17-18 minutes. (may need slightly longer or less) Check on them at at 15-16minute mark to access. When a toothpick inserted into the center come out clean or with moist crumb clinging to it, remove from oven.
Let cupcakes sit in pan for about 2 minutes before removing to a cooling rack to finish cooling completely.