Before you start, measure out the milk and stir in the vinegar - leave to stand and curdle whilst you get everything you need ready.

Preheat oven to 160˚C and line your cupcake tin with paper cases.

Measure all the dry ingredients into a bowl and whisk to combine. Rub in the butter until it is well dispersed throughout the flour mix (finer crumbs than for pastry making).

Crack the eggs into the curdled milk and add the vanilla extract and food colouring - whisk well to combine then pour in a steady stream into the flour mix. Beat until just smooth - don't overwork the batter!

Scoop into your prepared tin using an ice cream scoop (my 45ml one is useful here but make sure you only fill to halfway, 2/3 maximum or you *will* get muffin tops!) and bake for approx. 25 minutes until risen and when gently pressed, the cupcakes bounce back.

Leave to cool and when cold, make the marshmallow.

Place the gelatine sheets in a bowl of cold water (just enough to cover) and leave to one side.

In a heat proof bowl, add the egg whites, vanilla/caster sugar, salt and 1 tbsp of water and place over a pan of simmering water making sure the base does not touch the water.

Using a handheld electric whisk, beat the marshmallow ingredients until thick and fluffy - they will look like white patent leather (all glossy) and be reasonably stiff. This could take 8 minutes or so. Take off the heat.

Squeeze the water out of the gelatine and drop the leaves into the marshmallow and continue whisking until the bowl is cool and the mixture much thicker and stiffer - it will feel increasingly heavy on the whisks as it approaches being ready.

Immediately scoop into a large piping bag with either the end cut off or a large plain nozzle (at least 1.5cm wide) and pipe a generous amount of marshmallow on top of each cupcake. Hold the bag vertically and for a fat ghost, don't pull up too much or too quickly (as this will give a tall skinny ghost instead!).

By the time you have finished piping, you should be ready to paint chocolate faces on the ghosts - I leave the bowl of chocolate resting in another larger bowl of recently boiled water (don't let any water splash into the chocolate or it will seize) so that it is molten whilst you work with it. Use a skewer to paint two eyes and a mouth (get creative and give them personalities if you like!). The marshmallow will be firm but tacky so use a light touch to give a neat finish.