Whether you make them yourself or buy them, tortillas are a fantastic convenience food, the basis of burritos, tacos, and quesadillas. (Vegetarians should beware that some traditionally made tortillas sold in Mexican or Latin markets may contain lard.) Flour tortillas are soft and subtle, almost neutral in flavor, and range in size from small (2 or 3 inches) to very large (12 inches or so, ideal for burritos). Corn tortillas are a bit harder to handle but better in every other way: They have better texture, more flavor, and are whole-grain. The best corn tortillas have a fresh corn flavor and a soft and pliable texture when raw. Both flour and corn tortillas are a breeze to make yourself (see page 595).
Beans are are the most traditional filling for wraps using tortillas, like tacos; rice is a modern but common addition. Be sure the beans are well seasoned and not too soupy. Add more texture by using firmer grains, like wheat berries, instead of rice.
Vegetables are another option, especially grilled or breaded and fried, giving tacos and burritos an irresistible crunchy-soft texture. You can use just about any vegetable you like (see “Grilling Vegetables,” page 166, and “Batter-Fried Vegetables,” page 159).
The least traditional fillings are not Mexican at all: tofu, seitan, and tempeh. Frying, baking, and grilling tofu or tempeh give them a meaty texture, and seitan offers a pleasantly chewy texture.
Then there are the toppings: Check out the raw and cooked salsas on pages 659 to 664 but consider, too, Crunchy Corn Guacamole (page 174) or Mexican-Style Quickest Pickled Vegetables (page 89). Shredded lettuce or radish, chopped tomatoes, grated cheese, sour cream or yogurt, and hot sauces are givens; serve them in bowls on the table for everyone to dress their own tacos and burritos as they like.