Preheat the oven to 425°F. Line a baking sheet with parchment paper.
In a large bowl, whisk together the flour and baking powder with 1/2 teaspoon kosher salt.
Using the large hole on the side of a box grater, grate in the cold butter. (Alternately, cut it into small cubes and add it to the bowl.) Using your fingers, work the butter into the flour mixture just until it’s the texture of wet sand.
Stir in half of the milk just until combined then stir in the remaining half.
Using an ice cream scoop (or two spoons), scoop out 1/4-cup portions of the dough onto the baking sheet, spacing the biscuits at least 2 inches apart.
Brush the tops of the biscuits with milk then bake them until pale golden and cooked through, 14 to 18 minutes. Remove the from the oven and serve.