Corn tortillas are easy to make at home, especially if you use a tortilla press (instead of a rolling pin) to flatten the balls of masa, or dough, into disks. (Tortilla presses are only for corn, not flour, tortillas, as the gluten in the wheat flour is too elastic and would not work in a press. Flour tortillas must be shaped with a rolling pin.) We tested four brands, made of wood, cast iron, cast aluminum, and plastic, pressing a dozen tortillas in each (and then browning them in a skillet).