Start by preheating your oven to 350°F. I line my muffin pan with cupcake liners to make cleanup easy and keep the cupcakes intact. This step ensures even baking from the start.
In a medium bowl, I whisk together the flour, cocoa powder, baking soda, and salt. This helps distribute the cocoa and leavening evenly so every cupcake rises the same.
In a larger bowl, I mix the oil and sugar until smooth, then add the egg, vanilla, and red food coloring. The batter should look vibrant and glossy at this stage.
I gently stir in the buttermilk and vinegar, which gives the batter its classic tang. These ingredients also activate the baking soda for a light texture.
The dry ingredients are added to the wet mixture and mixed just until combined. I’m careful not to overmix, as that can make the cupcakes tough.
I divide the batter evenly among the liners and bake for about 18 to 20 minutes. When a toothpick comes out clean, they’re ready to cool.
While the cupcakes cool, I beat the cream cheese and butter until smooth. Then I gradually add powdered sugar and vanilla until the frosting is fluffy and spreadable.
Once the cupcakes are completely cool, I frost them generously. You can pipe or spread the frosting depending on the look you want.