Preheat the oven to 425°F
Line a baking sheet with parchment paper
In a large bowl, whisk together 2 cups all-purpose flour, 1 tablespoon baking powder, 1 teaspoon sugar, and 1 teaspoon salt
Cut in 1/2 cup cold unsalted butter until the mixture looks like coarse crumbs
Pour in 3/4 cup cold milk or buttermilk
Stir just until the dough comes together
Turn the dough onto a lightly floured surface
Gently pat it into a 1-inch thick rectangle
Fold the dough over itself 2 to 3 times for flaky layers
Pat or roll the dough to about 1/2 to 3/4 inch thick
Cut biscuits with a round cutter without twisting
Place biscuits on the prepared baking sheet
Gather scraps and repeat as needed
Brush the tops with melted butter or milk
Bake for 12 to 15 minutes until golden brown
Serve warm