Begin preheating a dry cast iron griddle or skillet over the lowest heat setting.
Whisk or stir the dry ingredients together in a large bowl.
Massage the oil into the dry ingredients using your fingers until evenly distributed.
Add the water and knead with your hand until the ingredients are well combined. Form the dough into a ball; the dough will feel moist.
Cut the dough ball in half, then form each half into a log. Cut each log into 3 equal pieces. Form each piece into an even mound (see photo gallery). Cover all of the dough with a slightly damp kitchen towel (or paper towel) to keep from drying out.
By now your cast iron pan should be evenly warmed up. Turn the heat to medium-high so it gets hotter. The handle will even become hot, so use a pot holder and be careful.
While the pan is getting hot, press and/or roll the first mound into a thin six-inch circle Whether pressing with a tortilla press or rolling with a rolling pin, the dough should be between two pieces of parchment paper.
Place the round onto the griddle/skillet being careful not to wrinkle. After about a minute it will form bubbles; that's your signal to flip.
After you flip the tortilla, watch for more bubbles to form on the second side. When you see bubbles, flip again and cook for 5 to 10 more seconds.
At this point the tortilla will be floppy and easy to roll, albeit a bit undercooked. This level of doneness is perfect if you plan on making quesadillas, enchiladas, or a similar baked dish (if filling and rolling – do so while the tortillas are still warm since they will be a bit harder to roll when completely cooled).
If you don't plan on making quesadillas, enchiladas, or the like – I suggest cooking each side a bit longer until dark spots form. Remove the tortilla from the pan and cool single layer.
Repeat with the rest of the dough.