Preheat oven to 375°F.
Line baking sheet with parchment.
In a large bowl combine flour, salt, baking powder, and sugar.
Work the butter in using a pastry knife or your fingers. Can use a food processor if you don't mind the hassle of cleaning it up.
Add 112 grams (~½ cup) of the buttermilk over the whole mixture and mix quickly for 15-20 seconds. If it's not a cohesive dough and seems too dry, add a little more buttermilk a teaspoon at a time.
Place the dough on a lightly floured surface. Work into a rough rectangle ~¾-inch thick. Fold into thirds, then roll out until ~¾-inch thick again.
Cut into circles with a biscuit cutter or just cut into even rectangles with a bench knife. (If using the biscuit cutter you'll have to re-knead and re-fold and re-cut and throw away some and can you guess which method I prefer?)
Put onto your parchment-prepared pan with the bottom now on the top (to give the top an even look). Brush with milk or remaining buttermilk for browning. (Brush with melted butter halfway through baking if you're looking for adoration.)
Bake for 15-20 minutes until lightly browned. Remove from oven and serve warm.