Place flour, baking powder, and salt in the bowl of a large food processor. Pulse a few times to combine.
Cut ½ cup (one stick) cold butter into small chunks. Add butter to the food processor bowl. Pulse about 12 times, or until butter breaks up into pea-sized pieces.
Add the milk to the food processor and pulse until the mixture forms coarse crumbs. Do not over-process!
Dust your work surface with about ¼ cup flour.
Dump the biscuit dough onto the work surface and form a square. Fold the square in half and press down to flatten slightly. Repeat folding and flattening about 16 times. (Don't skip this step! It's what gives the biscuits their flaky layers.) Add more flour to the work surface if needed (if the dough begins to stick).
Roll out dough to about ½ to ¾ inch in thickness. Try to make the thickness as even as possible.
Melt 2 tablespoons butter and add to each skillet you'll be using. If you don't have a cast iron skillet, you can use a pie dish.
Cut out biscuits with a biscuit cutter (3 inch size recommended). Try not to twist the biscuit cutter.
Add biscuits to the pan. It's OK if they're touching slightly.
Bake for about 20 minutes or until biscuits are golden brown. Brush with another 2 tablespoons melted butter after removing the biscuits from the oven.