Heat the oven to 430°. Mix together the flour, baking powder and salt in a large stainless-steel bowl. Cut 4 tablespoons of the butter into pats and incorporate into the flour mixture with a pastry blender until the mixture has a crumb-like consistency.
Make a well in the mixture and add the half and half. Mix all the ingredients together until fully incorporated and the dough sticks to a spoon.
Prepare a floured surface and place the dough on it. Sprinkle a bit of flour on the top of the dough and fold the dough over itself 3 to 4 times. Form a ball and flatten it with your hands to a ½-inch thickness.
Place the remaining 2 tablespoons of butter in a cast-iron skillet and melt it over low heat for about 2 minutes. Remove from the heat. Use a large biscuit cutter to cut out the biscuits.
Dab each biscuit in the melted butter, then turn over so the buttered side is up. Place the biscuits about ¼-inch apart in the skillet and bake for 20 minutes.