Line cupcake pan with liners.
Whisk the flour, sugar, baking soda, cocoa and salt in a large bowl and set aside.
Whisk the buttermilk, oil, vinegar and vanilla in a large bowl, then slowly whisk in the dry ingredients mixture.
Stir until combined, then add in the food coloring.
Fill the cupcake liners 2/3 full and bake for 15 minutes.