If no buttermilk, combine 1 Tbsp lemon juice or vinegar with regular milk to reach 0.75 cup (180ml) and let sit 5 minutes. For quicker butter incorporation, use a food processor by pulsing cold, cubed butter with dry ingredients. If no biscuit cutter, cut the 0.75-inch thick dough into 2-inch squares with a knife to avoid re-rolling. Dough can be prepared and cut up to 24 hours ahead; chill covered on a baking sheet and bake straight from the fridge, adding a few minutes to bake time. Overmixing dough develops gluten and leads to tough biscuits; mix only until just combined. Use very cold, grated butter for light and airy texture. Avoid twisting the biscuit cutter as it seals edges and prevents proper rise; press straight down and lift.