Step 1: Preheat the Oven

• Preheat your oven to 200°C (180°C fan) or 400°F.
• Lightly grease a baking tray or line it with parchment paper.

Step 2: Mix the Dry Ingredients

• In a mixing bowl, sift together the self-raising flour, baking powder, and salt.
• Add the mustard powder if using, for extra depth of flavor.

Step 3: Rub in the Butter

• Add the cold butter cubes to the flour mixture.
• Using your fingertips, rub the butter into the flour until the mixture resembles breadcrumbs.

Step 4: Add the Cheese

• Stir in the grated cheddar cheese, ensuring it’s evenly distributed.

Step 5: Mix the Wet Ingredients

• In a separate bowl, whisk the egg and milk together.
• Gradually add the mixture to the dry ingredients, stirring until a soft dough forms.

Step 6: Shape the Scones

• Lightly flour a work surface and roll out the dough to about 2 cm (¾ inch) thick.
• Use a round cutter to cut out scones and place them on the baking tray.

Step 7: Brush and Top with Cheese

• Brush the tops with a little extra milk or beaten egg for a golden finish.
• Sprinkle some extra grated cheese on top of each scone.

Step 8: Bake Until Golden

• Bake for 12-15 minutes, or until the scones are golden brown and well-risen.

Step 9: Cool and Serve

• Allow the scones to cool on a wire rack for a few minutes before serving.
• Enjoy warm with butter, chutney, or a bowl of soup.