1. In a large bowl or stand mixer, first cream the butter and zest of 1 lemon for 1 minute to soften and then add the sieved icing sugar.

2. Whisk together for 3-5 minutes until pale and fluffy. (You can either use a handheld whisk or a stand mixer.)

3. In another bowl, sieve the plain flour, cornflour and salt until mixed.

4. Add the flour to the butter mixture and mix until it is just clumping and coming together. Stop at this point to avoid over mixing.

5. Using the warmth of your hands, bring the dough together until it forms a ball. Don’t over handle it.

6. Wrap the dough in clingfilm and place it into the fridge for 30 minutes.

7. Preheat your oven to 160 degrees Celsius.

8. Line 2 baking trays with parchment paper.

9. Remove the dough from the fridge and roll it out to 1cm in height, between two sheets of parchment paper. Using parchment paper, means there is no need to use extra flour on a work surface or on a rolling pin.

10. Cut out desired shapes and place on the prepared baking sheets. Bring the scraps of dough together gently and re-roll. Shortbread doesn’t like being handled so keep the re-rolling to a minimum. For very sharp, well defined edges, place the tray of biscuits in the freezer for a further 10 minutes or the fridge for 30 minutes. (Be aware, if freezing for 10 minutes, the biscuits may require a slightly longer cooking time.)

11. Bake for 16-18 minutes until the biscuits are lightly coloured. ( you may need to bake for 18 – 20 minutes if they have been placed in the freezer for 10 minutes)

12. Allow to cool on the tray for 5 minutes before placing on a cooling rack to cool completely.

Decoration.
Add 1 tablespoon of lemon juice to 100g of icing sugar and mix well until there are no lumps. The consistency should be loose enough to pipe but thick enough to hold its shape. Using a piping bag, pipe lines across the cold biscuits. Allow the icing to set.