Preheat your oven to 350 degrees. Line the bottom of three 8 inch cake pans with parchment and grease the sides.
In the bowl of your electric mixer whisk together your flour, sugar, baking soda, cocoa, corn starch and salt. Grab a large measuring cup and combine the oil, eggs, buttermilk, food color, extract, and vinegar. Slowly mix into the dry ingredients.
Divide your batter evenly between your prepared pans. Bake 30 minutes, or until a toothpick comes out clean.