Pour Masa Harina slowly into the warm water while gently kneading the dough together with your fingers or a fork.
The dough should just hold together and be manageable without sticking. It shouldn't be kneaded thoroughly.
Form a number of balls, approximately 4 cm in diameter (about 35 grams), and let them rest for 10 minutes, preferably under a damp cloth.
Heat a cast iron skillet and make the tortillas one at a time: Place a dough ball in a tortilla press and press flat so the dough reaches the edge of the press.
Cook the tortilla on the skillet for 30-60 seconds on each side until the dough is cooked and starts to color here and there.
Place the finished tortillas in a stack in a breadbasket wrapped in a cloth to keep them warm and soft.
Note: Masa Harina tortillas dry out quickly, so it's important that they are covered with a damp cloth.