Chocolate strawberry sandwich biscuits

1. Preheat the oven to 180°C, gas mark 4 and line two baking trays with parchment.

2. Put the butter and both sugars into a mixing bowl. Beat together using a wooden spoon for a few minutes until slightly paler in colour, then mix in the vanilla and egg. Gradually add the flour and cocoa powder, beating as you go until the mixture is evenly combined and starts to clump together. Bring it together with your hands, wrap in clingfilm and chill for 30 minutes.

3. Remove the dough from the fridge, then roll out between two pieces of clingfilm to a 5mm thickness. Use a 4-5cm round cutter to cut out as many circles as you can (about 40). Aim for an even number. Arrange on the trays and bake for 12-14 minutes, then leave to cool on the trays for a few minutes, before moving to a wire rack to cool completely.

4. To make the buttercream, beat together the softened butter and icing sugar until smooth and light. Beat in the strawberry purée, then spoon into a piping bag and chill for at least 30 minutes or until needed. Pipe a circle of icing onto half the biscuits then sandwich with the other biscuits.

5. Melt the chocolate and dip half of each biscuit sandwich. Place onto a sheet of baking parchment and sprinkle with strawberry pieces. Leave to set. Store in an airtight container for up to 3 days.