Yield: 12 muffins
1 cup water, at room temperature
1 cup milk, at room temperature
1 scant tablespoon active yeast
1 tablespoon granulated sugar
2 tablespoons unsalted butter, at room temperature
2 teaspoons kosher salt
5 cups (approximately) unbleached bread flour
cornmeal for dusting
Combine the water, milk, yeast, and sugar in the bowl of an upright electric mixer. Add the butter, salt, and flour to the bowl, and using the dough hook attachment, knead the dough on medium for 10 minutes. Transfer the dough to a bowl that has been lightly oiled. Cover the bowl with plastic wrap and allow the dough to ferment at room temperature for 60-90 minutes, or until it has doubled in size.
Divide the dough into 12 equal pieces, shape them into balls, and gently press them down to form discs about 1-inch thick. Sprinkle a liberal amount of cornmeal on a baking sheet. Transfer the muffins to the baking sheet, allowing a couple of inches room in between each muffin. Dust the tops of the muffins with flour or cornmeal, and then loosely cover them with plastic wrap. Allow the muffins to rest for 45-60 minutes, or until they have doubled in size.
Heat a cast iron skillet over low-medium heat. Gently transfer a few of the muffins to the skillet and cook them until the bottoms are golden brown (4-5 minutes), and then carefully turn them over with a spatula and cook them on the other side. Transfer the cooked muffins to a wire rack or clean cloth and allow them to cool at least twenty minutes before serving.