Pre-heat the oven to 180c, Mix the sugar and flour together in a mixing bowl.

Cut the butter into small chunks and add to the flour and sugar, rub together until the mixture resembles breadcrumbs.

Cut the chocolate into small chocolate chip chunks and add to the mixing bowl.

Making a well in the middle of the mixture add in the tablespoon of water and with a table knife, bring the mixture together, then with your hands form into a soft dough, be careful not to over handle/work the mixture as it will become tough.

Sprinkle the work surface with plain flour, then with a rolling pin roll the dough out until around 1cm in thickness.

With a small round cutter, cut the dough into around 14 biscuits and place onto a baking tray, using the off cuts, bring together to reform the dough, then roll out and cut again to make around 4-6 extra shortbreads.

Place the shortbreads in the oven for 16-18 minutes, once cooked, remove from the oven and cool for 5 minutes, then sprinkle the biscuits with caster sugar to finish before serving.