Instructions:
- Preheat oven to 425°F (220°C). Line a baking sheet with parchment paper. Keep buttermilk very cold.
- Whisk together the flour, baking powder, sugar, and salt in a large bowl.
- Add the very cold cubed butter to the dry mixture. Use a pastry blender or your fingertips to quickly cut the butter into the flour until the mixture resembles coarse crumbs with some pea-sized pieces remaining.
- Pour in the cold buttermilk gradually, mixing gently with a fork just until the dough just comes together. Do not overmix; it should look shaggy.
- Turn the dough out onto a lightly floured surface. Gently bring the dough together into a rough mass. Pat into a rectangle, fold it over itself like a letter, and repeat this folding/patting process 2–3 times to build layers.
- Wrap the dough in plastic wrap and chill for 15 minutes, flattening slightly into a 1-inch thick disk.
- Roll the chilled dough out to a uniform thickness of ¾ inch. Using a 2-inch biscuit cutter, press straight down through the dough without twisting. Place biscuits onto the prepared baking sheet, touching slightly for softer sides.
- Brush the tops lightly with melted butter, if desired.
- Bake for 12–15 minutes, or until the biscuits are dramatically risen and golden brown on top.
- Cool slightly on a wire rack, then serve warm immediately.