01 - Preheat oven to 400°F and line a baking sheet with parchment paper.
02 - Whisk together flour, baking powder, salt, and black pepper in a large bowl.
03 - Add cold, cubed butter and use a pastry cutter or fingertips to blend until mixture resembles coarse crumbs.
04 - Stir grated cheddar and chopped chives into the flour mixture.
05 - Whisk milk and egg together in a small bowl, then pour into dry mixture and stir gently until just combined, avoiding overmixing.
06 - Turn dough onto a lightly floured surface and gently pat into a 1-inch thick round.
07 - Cut dough into 8 wedges, arrange on baking sheet, and brush tops with 1 tablespoon milk.
08 - Bake for 16–18 minutes or until golden brown. Transfer to a wire rack to cool briefly before serving.