Makes 30-40 shortbreads
- 150 grams plain flour
- 75 grams grated parmesan
- 100 grams soft unsalted butter
- 1 large egg yolk
- Mix all the ingredients together – using bowl and spoon, electric mixer or food processor – until a golden dough begins to form a clump.
- Turn it out onto a surface and knead for about 30 seconds until smooth, then divide into two.
- Take the first half and, using your hands, roll it into a cylinder about 3cm / 1¼ inches in diameter. Make sure the ends are flat so the cylinder resembles a roll of coins. Now roll this up in a piece of clingfilm, twisting the clingfilm at the ends, like a Christmas cracker, and put the roll in the fridge, then proceed in the same way with the remaining half of the dough.
- Preheat the oven to 180°C/gas mark 4/350ºF while the wrapped cylinders of dough rest in the fridge for about 45 minutes, by which time you should be able to cut them into thick slices easily: aim for about 1cm (½ inch) thick.
- Arrange on a baking sheet lined with baking parchment, and put in the oven for 15–20 minutes, when they should be slightly turning pale gold at the edges.
- Remove from the oven, then leave to cool before eating.