Combine the masa and salt in a bowl; stir in the oil until well combined. Slowly stream in water while mixing with your hand until the dough comes together into a ball.
Turn the dough int a lightly (masa) floured surface and knead until its smooth and elastic (not sticky) - just a minute or two. Leave uncovered in bowl, and let rest at room temperature for at least 30 minutes or up to a few hours.
Roll into golf sized balls (you're shooting for 12 to 16 tortillas total) Put them between modified zip top (cut the sides and top off of a gallon zip top), and press them in a tortilla press, or roll them out/press with your hands to a diameter of 4-6 inches. Do this one at a time as you cook them.
Heat cast iron skillet over medium-high heat. Cook the tortillas, 1 or 2 at a time, until brown spots appear on the bottom; usually about a minute. Wrap the cooked tortillas in a towel to keep them warm. Serve immediately or cool and store tightly wrapped in a fridge for a few days.