These chocolate orange shortbread biscuits are rich, crumbly and full of flavour, combining the depth of cocoa with the brightness of fresh orange zest. They’re easy to slice and bake, and the dough keeps its shape well, making this a straightforward but rewarding biscuit to prepare.
Put the sugar in a bowl and add the finely grated orange zest. Rub together with your hands to help release the citrus oils.
Add the flour and cocoa and stir well.
Cube the butter and add to the bowl.
Rub the mix through until you get an even crumb.
Add the vanilla extract and 1 tbsp of juice from your oranges and cut through with a cutlery knife. Give a little bit of the mixture a squeeze. If it comes together, it’s ready. If it’s dry and sandy, cut in up to another 1 tbsp of juice.
Gather up the pieces and knead together only as much as it takes to get a smooth ball of dough.
Roll the dough into a cylinder with a length of 30cm (12 inches) and a diameter of 5cm (2 inches). Wrap in greaseproof paper or plastic wrap and place in the fridge to rest and chill for 15 minutes.
While the dough chills, preheat the oven to 170C (150C fan / 340F).
Slice the dough into 1 cm cookies.
Place them on a lined baking tray and prick each one a few times with a fork.
Bake for 20-25 minutes until dry on the surface - they won't crisp up until they cool.