Lightly butter a 12-inch cast iron skillet or Dutch oven.

Pour the buttermilk into a large bowl.

In a small bowl or measuring cup, dissolve the yeast in the warm water with 2 tablespoons of the sugar and let set about 3-5 minutes. Mix the yeast mixture into the buttermilk. Whisk in the remaining 2 tablespoons of sugar.

Whisk in the baking powder, baking soda, salt, and oil. Slowly stir in enough flour to form a soft dough that is no longer sticky.

Turn the dough out onto a floured surface and roll out to about ½- inch thick. Cut out using a biscuit cutter. Gather up the scraps, roll out again, and cut.

Pour the melted butter into the skillet or Dutch oven. Dip both sides of one dough round in the butter and fold in half, like a taco (you can also leave flat like a regular biscuit as seen in video). Place the biscuits in the baking pan or skillet close together and repeat with the remaining rounds.

Cover and let rise in a warm place for about 40 minutes, or until nearly doubled in size.

About 20 minutes before baking, preheat the oven to 350°F with a rack in the middle.