- Preheat oven to 400 degrees. In a large bowl, whisk together flour, baking powder, sugar, and salt.
- Using a box grater, grate frozen butter into flour mixture, tossing after each quarter stick of butter to coat butter shards with flour. Toss to combine.
- Stir in 1¾ cups of buttermilk and, using large strokes and stirring from the bottom up, stir just enough to combine the mixture into a crumbly mass, 20 to 25 strokes. If dough does not come together, stir in more buttermilk a tablespoon at a time, just until mixture barely holds together.
- Dust a clean work surface with flour. Scrape dough onto floured surface, gather into a ball, and gently knead with the palms of your hands about 10 times, just enough to form a cohesive ball. Sprinkle a little more flour onto dough and gently roll or pat to an even ¾-inch thickness.
- Dip a 2½-inch round biscuit cutter in flour and, punching straight down without twisting, punch out the biscuits Punch rounds as close together as possible to use as much dough as possible in the first roll (re-rolled dough is always chewier).
- Place biscuits on a baking sheet. Bake 20 minutes. Let biscuits rest 5 minutes before serving. The resting time allows the team inside the biscuit to finish cooking the center.