Preheat the oven to 180℃/356℉. Line a 6 mold muffin tray with baking spray and/or muffin liners.
In a large bowl, mix flour, sugar, cacao powder, baking soda, and salt together.
In a separate bowl, or jug, add buttermilk, oil, an egg, vanilla essence, red food colouring and vinegar together and whisk until well combined.
Add to the dry ingredients and using a spatula, mix until well combined and no flour pockets left.
Fill each about 1/3, evening out the top and bake for 18-20 minutes. Remove and allow to cool down before icing.
In a medium bowl, whisk butter and cream cheese together until fluffy. Add the powdered sugar and slowly incorporate the sugar. Whisking until the frosting becomes fluffy and paler in colour.
Transfer the frosting into a piping bag and ice your cupcakes when ready. Garnish with grated white chocolate.