Rub the butter into the flour and other dry ingredients with your fingertips until the mixture resembles course breadcrumbs.
1 oz unsalted butter, 4 oz wholemeal flour, 4 oz plain flour (all purpose flour), ½ tsp bicarbonate of soda (baking soda), 1 tsp cream of tartar, ½ tsp sea salt, 1 tsp mustard powder, ¼ tsp cayenne pepper
Stir in the cheese, then mix in the egg, yoghurt and enough water to form the mixture into a soft dough (another 1-2 tbsp).
3 oz cheddar cheese, 1 egg, 2 tbsp Greek yoghurt
Working quickly with your hands, bring the mixture together and form it into a round about ¾ inch thick. Cut out into 8 rounds.
Bake at 200℃ (400℉, Gas 6) for 12 to 15 mins or until the scones are golden and sound hollow when their bases are tapped.
Notes
For a spicier take on these scones, swap the mustard and cayenne for a teaspoon of your favourite chilli spice mix. Harissa, zhug and piri piri are all good.
If you don't have cream of tartar, use 2 tsp baking powder and omit the bicarbonate of soda.
Please note: calories and other nutritional information are per serving. They're approximate and will depend on exact ingredients used.