Preheat and prepare: Preheat your oven to 450°F (230°C). Prepare a baking sheet with parchment paper or grease lightly.
Cut in the butter: In a large mixing bowl, cut the cold butter into small cubes. Use a pastry cutter or your fingers to work the butter into the flour mixture until it resembles coarse crumbs.
Combine dry ingredients: Add the flour, baking powder, sugar, and salt to the bowl with the butter. Mix gently until combined.
Add buttermilk: Pour in the buttermilk and stir until the dough just comes together. It should be slightly sticky but manageable.
Form biscuits: Turn the dough out onto a lightly floured surface. Gently pat the dough into a rectangle about 1-inch thick.
Cut out biscuits: Using a round biscuit cutter or the rim of a glass, cut out biscuits and place them on the prepared baking sheet. Gather any remaining dough, gently pat it out, and cut out more biscuits.
Butter bath: Melt the remaining butter and pour it over the tops of the biscuits.
Bake: Bake in the preheated oven for 12-15 minutes or until the biscuits are golden brown on top.
Serve warm: Remove from the oven and let cool slightly on a wire rack. Serve warm with additional butter or your favorite jam.
Enjoy these delicious and fluffy butter swim biscuits!