Prepare two baking trays by lining them with greaseproof paper/baking parchment.

In a large bowl, cream together the butter and sugar until light and fluffy.

Add the egg and the vanilla and beat in well.

Sieve in the flour and baking powder. Add the salt and beat in until a dough has formed.

If the mix seems more soft than dough-like, add more flour gradually, 1 tbsp at a time. Do this until a firmer dough has formed.

Tip out onto a clean and floured surface and bring together into a disc. Flour a rolling pin and use this to roll the dough out until around ½ cm in thickness.

Using a standard sized round cookie cutter, cut out 24 biscuits and lay in rows of 4 (across) by 3 (down) on each tray. You will need to bring the dough together and roll back out again a couple of times to do this.

Preheat your oven to 180°C [350°F] or 160°C fan.

Once up to temperature, place your trays on the middle shelves and bake for 8 – 10 minutes, until golden. They will continue to bake on the tray so don’t be tempted to bake for longer!

Once baked, leave to cool on the trays completely.

While your cookies are cooling, begin preparing your decorations.

Split the sugar into two bowls (6 in each). Add 1½ tbsp water and mix it into one bowl of sugar to create a thick paste. Do the same with the other.

Add a few drops of green food colouring to one bowl and mix it in until smooth. Adjust the strength of the colour if necessary.

Repeat with the other bowl, adding the red food colouring instead.

Once your Grinch cookies are completely cool, begin spooning the icing mix onto your biscuits. There is no rhyme or reason with this part: just have fun! I recommend starting small and using the spoon to spread the icing to avoid it running off the biscuits too much.

Finish with the Christmas sprinkles and edible glitter as you spoon on the icing. If you have other pairs of hands helping out, you could do a Christmas factory line!

Once decorated, allow the biscuits to set for *as long as you can* before enjoying. Allow to set until solid (around 5 hours) before piling on top of each other to store in an airtight container.