Heat milk, bacon fat, kosher salt, and shortening in a plastic bowl in the microwave in 30-sec bursts until hot.

Add in the flour, stirring with a spoon. Knead until you can handle it with your hands. Kneed it with your hands for 3 minutes.

(This dough doesn’t have to be rested.) Separate into 6-8 balls. Before cooking, squish them out flat into little circles with the palms of your hands or roll with a rolling pin. They should be close to an 1/8 inch thick.

In a buttered cast-iron skillet over medium-high heat, fry each tortilla 2-4 minutes on each side. Salt each side well for the best flavor. Allow to cool. Repeat with remaining dough. Grease pan again as necessary through frying the raw tortilla circles. This can be done with bacon fat, butter, or oil.