01 - Preheat oven to 350°F. Line a 12-cup muffin tin with paper liners.
02 - In a medium bowl, whisk together flour, sugar, cocoa powder, baking soda, and salt until combined.
03 - In a large bowl, whisk oil, buttermilk, egg, vanilla extract, vinegar, and red food coloring together until smooth.
04 - Add dry ingredients to wet ingredients and mix gently until just combined, avoiding overmixing.
05 - Divide batter evenly into cupcake liners, filling each about two-thirds full.
06 - Bake for 18 to 20 minutes, or until a toothpick inserted into the center comes out clean.
07 - Allow cupcakes to cool in the pan for 5 minutes, then transfer to a wire rack and cool completely.
08 - Beat cream cheese and butter together until smooth. Add powdered sugar, vanilla, and salt; beat on low until incorporated. Increase speed and beat until fluffy.
09 - Once cupcakes are fully cooled, frost generously using a piping bag or spatula.