Equipment: Tortilla press*
*I use a 7-inch cast-iron press, which should be easy to find for less than $20. Note that cast-iron can rust if not properly cared for; keep it dry, and lightly rub it with oil if you are storing the press for a long time without regular use.
Inspect the dough: Whether you’re using fresh masa or rehydrated masa harina, you want the texture to be as soft and moist as possible without sticking to your hands. If the dough develops small cracks when squeezed, it is too dry and needs more moisture. To correct this, knead water into the dough in 1 tablespoon increments until it becomes malleable and forms into a ball. Cover the masa with a damp towel.
Prepare the equipment: Set up a double griddle or two cast-iron pans over two burners. Heat one side of the griddle (or one pan) over low-medium heat and the other over medium-high heat for about 5 minutes. Cut two squares of medium-heavy plastic to fit the press (a freezer bag works nicely). Open the tortilla press and place one square on the bottom plate and the other on the top plate, making sure the plastic does not wrinkle.
Make a test tortilla: Grab a small handful of the masa and roll it into a sphere about the size of a golf ball. Gently flatten it into a rough disk with your fingers.
Position the tortilla press with the pressure handle on the side of your body that you favor—if you’re right-handed, the handle should be on the right. Open the press, keeping the plastic squares on each plate. Center the disk of masaon the bottom plate. Close the top plate, ensuring that the second piece of plastic lands squarely on top of the dough. Fold the handle and apply even pressure. Fold back the handle and open the press. Peel the top plastic from the tortilla. The tortilla should be 5 inches in diameter and about 1/8 inch thick.
Pick up the bottom plastic square with the tortilla stuck to it. If you’re right-handed, pick it up with your left hand; if you’re left-handed, pick it up with your right. Flip the tortilla over onto your empty palm; the upper edge should run along the tops of your index and middle fingers. Peel off the plastic.
Cook the tortilla: Position yourself over the cooler end of the griddle, with the tortilla draped over your palm and the top of your hand parallel to the hot surface. Bring the edge of the tortilla to the griddle and very quickly slide your hand out from under it; the tortilla should stick right away to the surface. If you’re too slow, the tortilla will fold and cook unevenly.
Cook for 15 seconds. The tortilla will begin to change color after 10 seconds. Using a metal spatula or your fingers, flip it onto the hotter side of the griddle and cook for 30 seconds. Flip the tortilla again, leaving it on the hotter side and cook for another 10 seconds before flipping a final time. Cook for an additional 10 seconds. When the tortilla is done, its edges will begin to release from the griddle and it may inflate slightly.
Taste your test tortilla: If the dough is too dry, the texture will be heavy and the edges will begin to crack. If needed, gradually add water to the remaining dough in 1 teaspoon increments until it is moist and malleable.
Once you’re happy with the texture, divide the remaining dough into 12 equal balls and repeat the process of pressing and griddling the tortillas. Store the cooked tortillas in an insulated container so that they retain their heat until ready to serve.