Step 1

Preheat the oven to 230°C (Gas 8). In a large bowl, or the bowl of a food processor, mix together the flour, baking powder, and salt. Add the butter and rub it in, or pulse-blend, until the mixture resembles fine breadcrumbs.

Step 2

Make a well in the centre of the flour mixture and stir in the buttermilk. You will need to use your hands to bring the dough together. Gently knead the mixture on a floured work surface to form a soft dough.

Step 3

Gently roll the dough out to a thickness of 3cm. Cut rounds out of the dough with a 7cm biscuit cutter. Gently bring the dough back together and re-roll it to cut out as many as possible.

Step 4

Brush each biscuit with a little of the egg. Bake in the top of the oven for 10-12 minutes, until they have risen and are golden brown.