In a medium bowl, mix together with a wooden spoon masa harina and hot water until thoroughly combined.
Turn dough onto a clean surface and knead until pliable and smooth. If the dough is too sticky, add more masa harina; if too dry, sprinkle with water. Cover dough tightly with plastic wrap and allow to stand for 30 minutes.
Preheat a cast iron skillet or skillet to medium-high heat.
Divide dough into 15 equal-size balls, I use a cookie dough scooper and generously scoop, sometimes I get less than 15.
Using a tortilla press, I have one but you can just roll out with a rolling pin, I use parchment paper not wax paper but everyone else I know uses plastic wrap or Ziplock bags, use what works for you.
Immediately place tortilla in preheated pan and allow to cook for approximately 30 seconds, or until browned and slightly puffy. Turn tortilla over to brown on the second side for approximately 30 seconds more, then transfer to a clean towel and Repeat process with each ball of dough. Keep tortillas covered with the towel, I just fold the towel in half and place it on one half and cover with the other. This allows them to stay warm and moist until ready to serve.