2 cups dry masa harina (preferably Maseca or Bob's Red Mill)
Total time: 45 minutes
In a large bowl, combine 1¼ cups room-temperature water, salt, and oil. Stir in the masa, then work into a dough. Dough should be as moist as clay but not sticky. Press a piece flat between your fingers—if the edges crack, work ½ tsp. water into dough at a time, up to ¼ cup more if necessary.
Using your hands, roll dough into 1½" balls. Preheat a cast-iron frying pan over medium-high heat. Prepare a layer of foil or a tortilla warmer lined with a clean cloth to fold over cooked tortillas.
Line a tortilla press with a 6" square of plastic (cut from a thick shopping or freezer bag). Position a dough ball in center of press. Set another square of plastic on top and close the press, pressing gently, until tortilla is 4" to 5" in diameter.
Open press and carefully peel off top plastic square. Turn tortilla upside down onto your palm and gently peel off the other plastic square. If tortilla sticks to plastic, it is too wet; work a little dry masa into dough and roll and press again. Place tortilla in preheated frying pan and cook 1 minute, until a few small brown spots appear. Turn and cook on other side until firm, about 1 minute. Place in foil or warmer and repeat with remaining dough.
Tip: A tortilla press, available at home goods stores, makes shaping tortillas fast and easy. Alternatively, use a rolling pin.