Preheat your oven to 175°C (350°F). Line a muffin tin with cupcake liners. This helps cupcakes bake evenly and prevents sticking.

In a large bowl, combine flour, sugar, baking soda, salt and cocoa powder. Stir well to remove lumps and mix evenly.

In another bowl, whisk buttermilk, oil, egg, vanilla extract, red food coloring and vinegar. Mix until smooth and well combined.

Slowly add wet ingredients into dry mixture. Beat gently until smooth. Do not overmix or cupcakes may become dense.

Spoon batter into cupcake liners. Fill each liner two-thirds full. This allows space for rising while baking.

Bake for 18–20 minutes at 175°C (350°F). Insert a toothpick in the center. If it comes out clean, they are ready.

Remove cupcakes from the oven. Let them cool in the pan for five minutes. Transfer to a cooling rack and cool completely before frosting.

Beat cream cheese and butter until smooth and creamy. Gradually add powdered sugar and vanilla extract. Beat until fluffy and soft.

Spread frosting on cooled cupcakes using a spatula or piping bag. Decorate with red crumbs or sprinkles if desired.