Preheat the oven to 425°F. Line a sheet pan with parchment paper and set it aside.

Pour the flour into a large bowl. Cut the 6 tablespoons of diced, cold butter into the flour using a pastry cutter or two forks until pea-sized lumps remain.

Add 1/2 cup of buttermilk to the flour-butter mixture. Mix until a soft dough forms, adding more buttermilk (1/4 to 1/2 cup more) if needed.

Transfer the dough to a lightly floured surface. Knead the dough with your hands until it comes together, adding additional flour to prevent sticking.

Pat the dough to roughly 3/4-inch thickness.

Cut 10 biscuits from the dough using a 2-inch round biscuit cutter. Transfer them to the baking sheet with their sides touching each other.

Refrigerate the biscuits for about 10 minutes to firm the butter.

Brush the biscuits with 1 tablespoon of melted salted butter before baking them for 13-15 minutes, until risen and light golden brown.

Once baked, brush them with the remaining tablespoon of melted salted butter.