Preheat the oven to 350 degrees
Whisk together buttermilk, eggs, vegetable oil, vinegar and vanilla in a tall liquid measuring cup, set aside.
In a small bowl, add the cocoa powder and food coloring together, set aside.
In another bowl combine the flour, salt and baking soda, set aside. (Lots of setting aside : P)
With an electric mixer and a paddle attachment, beat the butter and sugar on medium high.
Reduce speed and then add the buttermilk mixture and flour in 3 additions, alternating.
Add cocoa mixture and beat on low until everything is incorporated.
Divide the batter into 2, greased 9-inch round pans.
Bake for about 20 to 25 minutes, try to take it out when the center is just a little wiggly. NOTE: Everyone’s oven bakes differently based on many factors, do not take the cake out of the oven until you feel it is cooked. Use the tooth pick method if you’re nervous to take it out a little before.