Preheat the oven to 200ºC/gas mark 6 and line the tin with the cupcake cases.
Put all the ingredients except for the milk in the processor and then blitz till smooth. Pulse while adding milk, to make for a soft, dropping consistency, down the funnel. Alternatively put all ingredients into a large mixing bowl and use an electric hand mixer. BY HAND using a bowl and wooden spoon, cream the butter and sugar, beat in the eggs one at a time with a little of the flour. Add the vanilla extract and fold in the rest of the flour, adding the milk to get the dropping consistency as before. Spoon into the cases equally.
Put in the oven and bake for 15-20 minutes until the cup cakes are cooked and golden on top, check to see if the cupcakes are ready by inserting a cocktail stick into one of the cupcakes. If it comes out dry then the cupcakes are done.As soon as possible, take the cupcakes in their cases out of the tin and let cool, on a wire rack.
For the buttercream icing, mix butter with the icing sugar and cocoa powder. Continue to mix until smooth adding the milk to loosen the buttercream.
Spread the chocolate buttercream using a palette knife on top of the cupcakes, creating a flat surface and smooth gently with the palette knife. If the buttercream sticks to the knife, heat the knife in a glass of hot water, wipe quickly and smooth the buttercream, repeat if necessary. Don’t worry too much as most of the buttercream will be covered with marshmallows!
Take some white mini marshmallows and cut in half diagonally across the middle. Take a sandwich bag and fill ¼ full with the yellow glimmer sugar and add the cut marshmallows. The cut side is sticky and will stick to the sugar. Gently push the marshmallow halves into the chocolate buttercream, starting at the outside edge of the cupcake with the ‘pointy’ part of the cut marshmallow pointing outwards. Complete the circle. Now create a second inner circle of petals in the same way.
Cover the centre with chocolate drops or chocolate flakes to complete your sunflower cupcakes.