Preheat oven to 450°F. Line a baking sheet with parchment.
Whisk flour, baking powder, baking soda, salt, and sugar.
Cut in cold butter using a pastry cutter until mixture resembles coarse crumbs.
Add buttermilk and stir just until dough comes together.
Turn onto floured surface. Pat to 1-inch thick.
Fold dough in half, pat down. Repeat 3-4 times (creates flaky layers).
Pat to 3/4-inch thick. Cut with 2.5-inch biscuit cutter.
Place biscuits touching on baking sheet (helps them rise tall).
Bake 12-15 minutes until golden brown.
Brush with melted butter immediately.
💡 Tips & Notes
Cold ingredients are essential! Some bakers freeze their butter and grate it. Don't twist the cutter - push straight down or your biscuits won't rise evenly.