In a food processor, pulse the flour, baking powder, salt, and sugar a couple times to combine.
Add the butter and pulse 7-10 times until the butter is completely distributed. You shouldn’t see any chunks of butter, and the mixture should have a sandy texture to it. Transfer to a large mixing bowl.
In a small bowl, whisk to combine the milk and egg. Save 2 tbsp of it for the egg wash later, and pour the rest into the mixing bowl with the dry ingredients.
Stir to combine with a spatula, until a rough dough forms.
Transfer to a lightly floured countertop and knead about 10 times until the dough comes together into a relatively smooth ball. Take care not to knead too much, or the dough will be tougher and not rise as high.
Roll the dough about an inch thick and use a 2.5″ cutter to cut about 7 circles. Re-roll the scraps and cut out another 2.
Place the scones onto a parchment or silicone mat lined baking sheet and brush the tops with the reserved egg wash.
Bake the scones for 13-15 minutes, until about tripled in height, and golden brown on the tops and bottoms.