Preheat your oven to 450°F (232°C).
In a medium bowl, whisk together flour, baking powder, sugar, and salt.
Pour in the buttermilk and stir gently just until combined-avoid overmixing to keep biscuits tender.
Pour the melted butter into an 8x8-inch baking dish, spreading it evenly across the bottom.
Transfer the dough into the pan and spread it out evenly with a spatula or your hands.
Score the dough into 9 squares using a knife (3×3 pattern).
Bake for 28 minutes, or until the tops are golden brown.
Allow the biscuits to rest a few minutes to soak up the butter before cutting and serving warm.
