Pre-heat the oven to 175°C (350°F) and prepare a muffin tin with cupcake cases.

Cream the butter and sugar and then whisk in the egg.

Add the flour, cocoa, baking powder, vanilla sugar, coffee and milk and whisk for a minute or two until well combined.

Blitz the Maltesers in a food processor until a mixture of fairly large pieces and fine powder are left (don't over work because it is nice to have little lumps of crunchy malt sweetness left). Gently stir half of the Maltesers into the batter and retain the other half for the frosting.

Pour the batter into nine or ten cupcake cases and bake for around 17-19 minutes. Remove from the oven and allow to cool completely.

For the frosting: Beat the butter and icing sugar together. If the mixture is too thick, add a little milk. Lastly, add the Maltesers and stir in. When the cupcakes are cool, spread the frosting over (or pipe it, if you prefer) and decorate with a couple of whole Maltesers. Enjoy!