Step 1: Preheat your oven to 425°F (220°C). Line a baking sheet with parchment paper.
Step 2: In a large bowl, whisk together the flour, baking powder, baking soda, and salt.
Step 3: Add the very cold butter pieces to the dry ingredients. Using a pastry blender, your fingertips, or two knives, cut the butter into the flour until the mixture resembles coarse crumbs with some pea-sized pieces of butter remaining.
Step 4: Pour in the cold buttermilk. Mix with a fork or your hands until just combined and a shaggy, slightly sticky dough forms. Be careful not to overmix.
Step 5: Turn the dough out onto a lightly floured surface. Gently pat the dough into a rough rectangle, about 1 inch thick. Fold the dough in half over itself, then pat it down again. Repeat this folding and patting process 2-3 more times to create layers. (This is the secret to flaky biscuits!)
Step 6: Pat the dough to a final thickness of about 3/4 to 1 inch. Using a 2.5-inch biscuit cutter, cut out rounds. Press straight down, do not twist, to ensure a good rise. Gather scraps, gently press together, and cut out any remaining biscuits. (Avoid overworking the scraps).
Step 7: Place the biscuits on the prepared baking sheet, ensuring they are slightly touching each other for a higher rise. Bake for 12-15 minutes, or until golden brown on top and cooked through.
Step 8: Remove from oven and serve warm. Enjoy with butter, jam, gravy, or your favorite toppings!