Directions

1. Beat the butter and sugar together until creamy, then mix in the rest of the ingredients. Add a splash of milk if the mixture looks a bit dry - it should come together as a dough.
2. Line three baking sheets, dust lightly with flour, then roll and pat one-third of the dough out to the thickness of a PS1 coin on each. Cover and freeze for 15 mins.
3. Heat oven to 180C/160C fan/gas 4. Slide the dough off the trays and put a new piece of parchment on each. Trim the edges of the dough to straighten, then cut into rectangles, roughly 6 x 3cm. Lift each one carefully onto the tray, leaving some space between them as they'll expand. Bourbons usually have a pricked pattern, so use a cocktail stick to do this if you want (not too many or they'll break up). Put the dough back in the freezer if it gets too soft.
4. Bake for 8-10 mins, then leave to cool on the sheet as the biscuits will be soft when they're hot. Sprinkle over some sugar.Will keep for a week in an airtight container.
5. Meanwhile, make the filling. Beat the butter and icing sugar together, then divide the mixture into three. Add the cocoa to one lot, a dot of pink colour to another, and leave the last one plain (add a little more icing sugar if you need to). Spoon each into apiping bagor a sandwich bag with the corner snipped off.
6. When the biscuits have cooled completely, pipe the icings onto half of them, then sandwich together with the other halves. Leave to set.