In her book this recipe is illustrated with step-by-step pictures.
1 1/2 pounds (675g) Tortilla Masa, about 2 1/2 cups
Water if needed
Work the masa with your hands to make sure the moisture is evenly distributed and there are no lumps or whole kernels that have escaped the grinding stones.
Here's a warning to save you a lot of tears about the first impossible tortillas: if the masa is too damp, then you will never be able to get it off the plastic bags (in the press). If this happens, flatten the masa and leave in an airy place to dry until manageable. If your masa is too dry, then it will crack and crumble as you attempt to make tortillas. Add some water, working it in well a little at a time. (I know from experience that a little water goes a long way and you can easily make it too wet.)
Either divide the masa into the number of tortillas you are going to make - but cover them with a damp cloth so they do not dry out while you are working with the first balls - or with more practice, just take off the lumps of the dough as you go along and keep the bulk of it covered while you work if the air is very warm and dry. Try to keep the balls as near the same size as possible. Mexican cooks are expert at this.
Heat the ungreased comal or griddle over medium heat. To test, the dough should sizzle slightly as it hits the hot surface. Line your tortilla press with two plastic bags. Place a ball of the dough on the bottom plate of the press and flatten it a bit with your hand. Close the top plate of the press down firmly - but don't put all of your weight on it - and flatten the tortilla very thin. Open the press up, and remove the top bag.
Lift up the bottom bag with the dough, and resting the dough on the inside of your fingers (do not rest the dough on your palm because it will be difficult to transfer onto the comal), carefully peel back the plastic bag. Take care to lay the tortilla on the comal and let it cook until the underside is just turning opaque and speckled with brown. Do not leave the tortilla to cook too much on the first side or it will be overcooked and inflexible.
Flip the tortilla over and cook a little longer on the second side. Flip it back again and continue for a few seconds more until the dough is cooked through and the top skin (ideally) puffs up. This will be the "face" of the tortilla, and since it is likely to flake off, it will always go inside when making a taco or enchilada. (Note: Any traditional Mexican cook will tell you that a tortilla should never be turned more than twice.)
Unless you are going to eat it right away, place the freshly made tortilla immediately on top of the rest wrapped in a thick cloth, or a cloth-lined basket, to keep them warm and flexible. This process does need some practice until you become adept at recognizing what the masa should ideally feel like, just the right heat under the comal, and the timing of the turns. When you have those mastered, it is a soothing, therapeutic sort of job after a possible frenzied first attempt.
Wipe off the plastic bags and reserve them for a lot of other tortilla making. Make sure the inside plates of the tortilla press are clean and place a double layer of paper toweling between them when storing the press. Wipe the comal off with a slightly greased paper and store.
Note: Tortillas can be made with Maseca, Minsa, or masa harina, but only use these dried corn products as a last resort. They do not have the same flavor or the texture of the real thing, and the tend to discintegrate when used for chilaquiles, tortilla soup, or casseroles.
Makes 15 5 1/2-inch tortillas.
From My Mexican Kitchen: Techniques and Ingredients by Diana Kennedy (Clarkson Potter, 2003) - reprinted with permission
101 Cookbooks http://www.101cookbooks.com/