Preheat oven to 425 degrees. Line two baking sheets with Silpats or parchment paper.Advertisement
In a large bowl, sift together flour, baking powder, baking soda, and salt.
Using a pastry cutter, two knives, or your fingertips, blend in 10 tablespoons chilled butter pieces until the mixture resembles coarse meal. Stir in buttermilk, and mix until dough holds together. Turn dough out onto a lightly floured surface, and knead briefly until smooth. Roll out the dough to a 1/2-inch thickness, and cut into rounds using a 2-inch biscuit cutter.
Place biscuits on prepared baking sheet. Prick the tops with a fork, and brush with melted butter. Bake until just lightly golden, 12 to 15 minutes. Transfer biscuits to a wire rack to cool.