Preheat the oven to 400 degrees F and line a baking sheet with parchment paper.
In a large mixing bowl, whisk together 2 cups all-purpose flour, 1 tablespoon baking powder, 1 teaspoon baking soda, ½ teaspoon cream of tartar, 1 tablespoon sugar, and 1 teaspoon salt.
Cut ½ cup cold salted butter (1 stick), diced into small pieces, into the dry ingredients using a pastry cutter, pastry blender, or two knives until the mixture resembles coarse crumbs.
Pour ¾ cup cold buttermilk into the bowl and stir just until a dough forms. Do not over mix. The dough will be sticky.
Transfer the dough to a lightly floured surface and gently roll or pat it out until it is approximately ½-inch thick.
Lightly flour the top of the dough to prevent sticking.
Use a 2½-inch to 3-inch biscuit cutter or the rim of a drinking glass to cut out the biscuits. Do not twist the cutter when cutting; gently lift or shake the biscuit free.
Place the biscuits on the prepared baking sheet, leaving a small amount of space between them.
Bake for 14 to 17 minutes or until the tops are lightly golden brown.
Let the biscuits cool for 5 minutes.
Brush the tops of the warm biscuits with 1 tablespoon melted butter.
Serve warm and enjoy.
Video
Notes
Store the leftover biscuits in an airtight container at room temperature for up to 1 week.