Preheat the oven to 350°. Grease 2 - 8" pans or 4 - 6" pans.
Cream together butter and sugar. Add eggs and continue to beat until incorporated.
In a small bowl mix cocoa, food coloring and water to make a paste. Add to the butter mixture along with the vanilla extract and mix to combine.
Add the buttermilk to the same bowl that you used to mix the cocoa and food coloring. Add the baking soda and stir to get all the color that was left behind.
In another bowl combine the flour and salt. Add to the butter mixture in three parts alternating with the buttermilk. Beat well.
Fold in vinegar.
Divide into greased pans and bake 25-35 minutes depending on the pan size. For cupcakes bake 16-18 minutes.
Invert the warm layers onto plastic wrap and wrap tightly. Freeze overnight or until ready to frost.
Cream Cheese Frosting
Remove the cakes from the freezer before starting the frosting to allow them to start thawing.
In the bowl of a stand mixer beat together the cream cheese and butter until smooth.
Slowly mix in the powdered sugar, vanilla bean paste and salt.
Level the cakes, if desired, and then fill and frost.
Cake should be served at room temperature. Store leftovers in the refrigerator.