Preheat Oven: Preheat oven to 200°C (400°F). Line a large baking tray with baking paper and set aside.
Mix Dry Ingredients: In a large mixing bowl, add the flour, baking powder and salt. Stir until combined.
Rub In Butter: Add the chilled cubed butter. Using your fingertips or a pastry cutter, rub the butter into the flour mixture until it resembles coarse breadcrumbs, this takes 1-2 minutes.
Add Cheese & Chives: Add the grated cheddar cheese and chopped chives and mix until evenly distributed.
Add Milk: Make a well in the centre and pour in the milk. Using a wooden spoon or spatula, gently mix until a rough dough forms. Do not overmix.
Bring Dough Together: Lightly flour your work surface. Transfer the dough onto the surface and gently knead just enough to bring it together. The dough is meant to be a bit shaggy, not well formed or smooth.
Shape Dough: Pat the dough into a thick disc approximately 3cm (1 inch) thick.
Cut Scones: Dip a 6cm (2 inch) round cookie cutter into flour and cut out scones. Transfer to the prepared baking tray, placing them slightly touching.
Re-roll Dough: Gather any remaining dough, gently pat it back into a 3cm thick disc and cut out additional scones.
Add Topping: Brush the tops of the scones with milk and sprinkle with the extra grated cheddar cheese.
Bake: Bake for 20–25 minutes or until the tops are lightly golden and the scones are cooked through.
Cool & Serve: Allow the scones to cool on the tray for 5 minutes before transferring to a wire rack. Serve warm with butter if desired.