In a large plastic or other mixing bowl, add the flour, salt, and the ball of vegetable shortening. Mix thoroughly until the mixture looks like fresh breadcrumbs.

Make a well in the center and add most of the hot water, reserving a little. If your flour is fresh, it may need less water due to its natural moisture.

Knead the dough as you would for pizza dough. If you need more water, add it a little at a time until you have a smooth, perfect dough. Your hands and the bowl should be very clean. Shape the dough into balls about the size of a large lemon; you should get about 30 tortillas from 1 kilogram (about 8 cups) of flour.

Roll the balls until smooth, then gently flatten them. Arrange the flattened balls in rows of three. If you used very hot water, you can roll them out right away; if you used warm or cold water, let them rest for 30 minutes.

To roll them out: Take a flattened ball and dust it with the reserved flour. Using a rolling pin, start from the center and roll outward, turning the dough as you go, until you have a circle about 10 to 12 inches (25 to 30 cm) in diameter.

If your tortillas aren't perfectly round, don't worry! In Sonora, we say they don't need to roll away. Lay them out on a table, one after another, then stack them up once they're all rolled out.

To cook: Heat a griddle or a large flat skillet (about 20 inches/50 cm wide) until hot. Place a tortilla on the griddle and cook for 30 seconds, then flip and cook for another 30 seconds. If it needs more cooking, repeat until done but not burned, or they'll turn hard. Repeat with the rest of the tortillas and enjoy.