1. Preheat the oven to 170°C fan. Line two large baking sheets with parchment paper.You will also need a medium cookie cutter (approx 5cm) and a smaller cookie cutter (star or heart shape) or any small round object.

2. In a mixing bowl, cream the butter and sugar together with an electric whisk until light and fluffy. Add in the egg yolk and vanilla extract.

3.Sift in the flour in two batches, using a wooden spoon or spatula to stir until the flour has been fully incorporated. The dough will come together to form a soft dough. Form into a shallow patty and wrap in cling film. Refrigerate for 15 mins.

4. Cut the dough into 4 pieces and roll each out on to a floured surface to a thickness of 3mm. Using a medium cookie cutter, dip it in flour, then stamp out an even number of cookie rounds (if the dough is very soft as you work with it, keep it chilled). Transfer half the rounds on to the first lined baking sheet for the bases (leave space between each). Use the smaller cutter to stamp out stars (or holes) in the centres of the remaining rounds for the tops. Transfer them on to the second lined sheet.

5.Chill the cookies in the fridge for 15 minutes before baking to reduce spreading (or place them in the freezer for 5 minutes if you have space).

6.  Bake in the preheated oven for 10-15 minutes or until the biscuits are golden in colour (place the tray with the bases on the higher rack).

7.  Once baked, remove from the oven and leave for 2 minutes before lifting them with a palette knife and allowing them to cool fully on a wire rack. Store in an airtight container until ready to assemble.

8. To assemble, spread a teaspoon of jam on to the bases. Dust the biscuit tops with icing sugar and sandwich on to the jammy covered bases. Fill the centres with an extra blob of any remaining jam.