Arrange the oven rack in the center of the oven, preheat to 350 degrees F. Grease a baking sheet with butter, oil, or cooking spray.
In a large bowl, whisk together the flour, baking powder, sugar, baking soda, and salt. Cut in the butter using a pastry blender, your hands, or two knives until the mixture resembles coarse meal and none of the pieces of butter is bigger than the size of a pea. Be careful not to overwork. Using a rubber spatula, fold the buttermilk into the flour mixture just until all of the flour is moistened.
Turn the dough out onto a lightly floured work surface. Knead lightly two or three times until the dough comes together (but should still be somewhat crumbly.) Gently pat the dough out until it's a 6-inch square. Cut the dough into 9 squares.
Place the biscuits onto the prepared baking sheet and bake until light golden brown and firm to the touch, about 12 minutes. Serve warm or at room temperature.
Store in a zipper bag on the counter. Reheat in a 350 degree preheated oven until warm for optimal texture the next day.