Heat oven to 350°F. Prepare three 8-inch round baking pans by spraying with baking and lining with parchment or spreading GOOP and lining with parchment.
In a 2 cup measuring cup (or medium bowl) pour buttermilk.
Add the vanilla, vinegar, and red food color to buttermilk and whisk to fully combine. Set aside.
In a large bowl add sugar, oil, and eggs and whisk together by hand until it is smooth and light yellow.
Add cake flour, cocoa, and baking powder to the sugar mixture and whisk until just combined.
Now add the buttermilk mixture and whisk until just combined. You do not want any lumps, but I do recommend being gentle with this batter.
Pour about 1 3/4 cup batter into each pan and bake for 22-32 minutes. When using my convection oven I will bake these at 325°F for 22 minutes. The cake is done when it does not appear wet on the top and if you press your finger gently in the center of the cake it feels firm.
Allow to cool in the pan for about 5 minutes, then invert onto a cooling rack. Chill cakes until ready to assemble.