Preheat the oven to 425°F degrees. Line a baking sheet with parchment paper and set aside.
Whisk the flour, baking powder, baking soda, sugar, and salt in a large bowl until combined.
2 cups all-purpose flour, 1 tablespoon baking powder, ¼ teaspoon baking soda, 1 tablespoon granulated sugar, 1 teaspoon kosher salt
Add in the butter and use a pastry cutter, fork, or your hands to work the butter into the flour until it is the size of peas.
7 tablespoons unsalted butter
Pour in the buttermilk and stir until just combined.
¾ cup cold buttermilk
Pour the dough out onto a floured work surface. Flouring the dough as needed, pat or roll it into a rectangle about ¾ inch thick.
Fold one side into the center, then the other, like a letter. Flatten the dough back out into a ¾ inch rectangle, and fold again. Repeat one more time for a total of 3 folds.
Flatten the dough out into a ¾ inch rectangle for one last time.
Use a 2-3 inch biscuit cutter to cut the dough. Cut straight down and do not twist the cutter. Reroll any scraps and continue cutting until all the dough is used.
Arrange the biscuits on the prepared baking sheet, brush the tops with buttermilk, and bake for about 15 minutes or until the biscuits are golden.
Let cool for 5 minutes before serving warm.