Combine, by adding about two thirds of the wet ingredients and beating until smooth. Then add the rest of the wet ingredients and beat until smooth again.
Scoop into muffin cases in a muffin tin and bake for between 17 and 19 minutes or until domed and springy on top.
To make the icing
While the cupcakes are cooking, make the icing. Beat together the sugar and butter until combined. (This may take a while and look grainy at first, carry on!)
Mix the cocoa with a little boiling water in a mug, just enough water to make a thick paste. Mix it until smooth and there are no lumps.
Beat the cocoa mixture into the icing.
If you want your icing to be most soft, fluffy and pipeable, add a teaspoon of boiling water at a time until it's the texture that you want.
To decorate, when the cupcakes are cool, put the icing into a piping bag fitted with a star piping nozzle (see notes).
Pipe a circle around the edge of the cupcake, continue with another circle on top, slightly smaller, and a finally tiny circle on top. Give the bag a squeeze, stop squeezing and pull the bag away quickly.
Portions - This recipe makes 12 SMALL cupcakes or 9 LARGE cupcakes (always my preference!) The ones in the photos are LARGE.Piping Nozzle - I almost always use a Wilton 1M nozzle, available on Amazon.