Preheat your oven to 400°F (200°C).

In a large mixing bowl, combine the all-purpose flour, baking powder, granulated sugar, and salt. Whisk together until well blended.

Add the chilled, cubed butter to the dry mixture, and work it into the flour until the mixture resembles coarse crumbs.

Make a well in the center and pour in the milk. Mix gently until the dough comes together, avoiding overmixing.

Turn the dough onto a lightly floured surface, knead gently a couple of times for a cohesive mixture, and pat it down until about 1-inch thick.

Cut the dough into triangles or circles using a sharp knife or a round cutter, and place the cut scones on a lined baking sheet.

Beat the egg and brush it lightly over the tops of each scone.

Bake the scones in the preheated oven for 15-20 minutes, or until golden brown on top.

Once out of the oven, let them cool slightly before serving warm with your choice of toppings.