In an ideal world, we'd make tortillas from fresh masa every time. Luckily, masa harina flour is a good alternative and makes any homemade tortilla a vast improvement over most store-bought ones.
Masa (wet) and masa harina flour (dry) differ from the cornmeal used in cornbread because they have undergone a centuries-old process called nixtamalization. This means that when the corn is just harvested, it’s dried and then soaked and cooked in an alkaline solution. This helps soften the corn while making it considerably more nutritious.
You can make a small investment in a tortilla press, which will produce perfectly uniform rounds, or press the tortilla dough between sheets of plastic wrap or wax paper underneath a skillet. Traditionally, a comal (a flat griddle) is used to cook the formed tortillas, but a cast-iron pan works just as well. Try to resist tampering with the cooking tortilla.
Tortilla makers pride themselves on turning the tortillas only once. To encourage an air bubble, which is the sign of a properly made tortilla, they tickle or poke the center, often with the end of a dry, clean towel. Whether or not your tortillas inflate on the griddle, they will certainly improve any meal, even a simple bowl of black beans with a bit of salsa. Once you get this recipe down, as long as you have masa harina on hand you will be able to make tortillas anytime.
To store the finished tortillas while making more, wrap them in a clean kitchen towel. They steam slightly and become even softer before serving. The tortillas can be made a few hours in advance, but wrap them in foil instead of a kitchen towel until ready to serve. Before serving, warm them in an oven (or toaster oven) set at 300°F for 10 minutes, or until warmed through.