Gluten-free lemon shortbreads

Line a 20 x 20cm cake tin with baking parchment. Blitz the flour, butter, half the icing sugar and the lemon zest together in a food processor until the mixture looks sandy. Add half the lemon juice and blitz again until the dough starts to clump together. At this stage, the dough will keep wrapped and frozen for up to two months. Heat the oven to 170C/150C fan/gas 3.

Press half the dough into the base of the tin using your fingertips, ensuring it’s in an even layer. Spread the curd over the dough, leaving a ½cm border of around the edge.

Roll the remaining dough into cherry tomato-sized balls, then press these into flat discs using your fingers. Arrange the dough discs over the layer of curd in a random patchwork pattern until completely covered. Bake for 35 mins until the shortbread is pale and lightly golden at the edges. Leave to cool completely in the tin.

Mix the remaining icing sugar with enough of the remaining lemon juice to make a pourable icing. Drizzle this over the cooled shortbread and leave to set, then cut into 16 squares. Will keep in an airtight container for three days.