Preheat and Prepare: First things first, preheat your oven to 200°C (180°C fan) and line a large baking tray with baking parchment.

Combine Dry Ingredients: In a large mixing bowl, whisk together the wholemeal flour, plain flour, optional protein powder, baking powder, salt, and pepper. This ensures everything is evenly distributed.

Rub in the Butter: Add the cold, cubed butter to the flour mixture. Using your fingertips, rub the butter into the flour until the mixture resembles coarse breadcrumbs with a few larger, pea-sized pieces of butter remaining. For a detailed guide on this technique, the rubbing in method is a fundamental baking skill.

Add Cheese and Chives: Stir the grated cheddar and chopped chives into the flour and butter mixture until they are just combined.

Mix the Wet Ingredients: In a separate, smaller bowl or a jug, whisk together the egg, Greek yoghurt, and 60ml of whole milk until smooth.

Form the Dough: Pour the wet mixture into the dry ingredients. Use a spatula or a round-bladed knife to mix everything together until a shaggy, soft dough begins to form. Be careful not to overmix at this stage. I find that just bringing it together is all you need.

Shape and Cut: Tip the dough out onto a lightly floured surface. Gently bring it together with your hands and pat it out into a rectangle about 2cm thick. Use a 6cm round cutter to stamp out your biscuits. You may need to press the scraps together gently to cut out the last few.

Bake to Perfection: Arrange the biscuits on your prepared baking tray. Brush the tops lightly with a little extra milk. Bake for 15-18 minutes, or until they have risen and are a deep golden brown on top. Transfer them to a wire rack to cool slightly before serving.