In a small bowl, whisk together flour, cocoa, baking soda, baking powder and salt. Set aside.
In a large bowl, using an electric mixer on medium-high speed, beat sugar, egg and oil for 1 to 2 minutes or until fluffy. Beat in food coloring and vanilla. Add flour mixture alternately with buttermilk, making three additions of flour and two of buttermilk and beating on low speed until smooth. Stir in vinegar.
If desired, place paper liners in wells. Fill each well with about 1 1⁄2 tbsp (22 mL) batter. Bake for 6 to 8 minutes or until a tester inserted in the center of a cupcake comes out clean. Transfer cupcakes to a wire rack to cool. Repeat with the remaining batter.
Frost with <a href="http://www.craftfoxes.com/dashboard/how_tos/cream-cheese-frosting--2">Cream Cheese Frosting</a>.
Tips: If you don’t have white vinegar, you can substitute cider vinegar in this recipe. Other vinegars, such as red wine vinegar or herb-flavored vinegars, will conflict in flavor and should not be used. No buttermilk on hand? Stir 1 1⁄2 tsp (7 mL) lemon juice or white vinegar into 1⁄2 cup (125 mL) milk. Let stand for 5 to 10 minutes or until thickened. Proceed with the recipe.