Preheat the oven to 200°C. Lightly oil a baking sheet.
Sift the flour into a mixing bowl and rub in the butter, using your fingertips, until it resembles fine crumbs. Reserve 25g of the cheese and stir the rest into the flour with a little salt and pepper.
Crack the egg into a jug, add 125ml of the milk and the mustard and whisk together using a fork, then gradually stir into the flour to make a smooth, soft dough.
Turn out the dough onto a lightly floured surface, knead lightly, then cut in half. Shape each half into a ball, flatten slightly and roll out to a circle 15cm in diameter. Cut each circle into quarters and arrange on
the baking sheet, leaving space between the quarters so that there is room for them to rise.
Brush the tops lightly with the remaining milk and sprinkle with the reserved cheese. Bake for 12–15 minutes until well risen and golden brown. Best served warm.
National Trust Book of Scones by Sarah Clelland (National Trust Books) - £9.99 - available at shop.nationaltrust.org.uk (ACE Best Product Award winner)
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