Preheat the oven to 425° F and line a baking sheet with parchment paper.
Cut the butter into pea sized cubes and place in the freezer. I also like to place my buttermilk in the freezer for a few minutes.
In a large bowl, whisk together the flour, baking powder, baking soda and salt.
Take the cubed butter out of the freezer and add it to the flour mixture. Using a fork or pastry blender, cut the butter into the flour mixture for about 4-5 minutes until it resembles pea sized crumbs.
Stir in the cold buttermilk until just combined. The dough should be sticky.
Turn dough out onto a floured surface and gently pat and shape the dough into a rectangle. Fold the dough into thirds like a letter. Turn the dough a half turn, pat in any remaining crumbs and flatten into a rectangle again. Repeat twice more, folding into thirds and patting it back into a rectangle.
Gently roll dough into about a ½-inch rectangle. Using a 2 ½-inch round biscuit cutter or Mason jar lid, push straight down into the dough and cut out 8-10 biscuits.
Transfer biscuits to prepared baking sheet and lightly brush with 1 tablespoon of buttermilk.
Bake at 425° F until golden brown, about 12-15 minutes.
Remove from oven and immediately brush the biscuits with 1 tablespoon of melted butter and sprinkle lightly with salt.
