How to Make It
Whisk together flour, baking powder, and salt in a large bowl. Add shortening; using your fingertips, incorporate into flour mixture until evenly combined. Add 1 1/4 cups water; mix with your hands until a sticky dough forms. Turn dough out onto an unfloured work surface. Using the heel of your hand, smear dough across work surface in a 10-inch-long layer. Using a bench scraper, scrape dough back into a ball. Repeat smearing and scraping process until dough becomes smooth and slightly sticky, about 5 minutes. Cut dough into 24 pieces (about 1 1/4 ounces each). Roll dough pieces into balls, and transfer to a baking sheet. Cover with plastic wrap; let stand at room temperature 30 minutes.
Heat a large cast-iron skillet over high until smoking; reduce heat to medium-low. Working with one dough ball at a time, roll dough out on an unfloured work surface to a very thin 7 1/2-inch circle. (Dough will stick to work surface.) Carefully peel dough off work surface; transfer to hot skillet. Cook until lightly browned in spots and pliable, 20 to 30 seconds per side. Wrap tortillas in a kitchen towel. Repeat process with remaining dough balls.