Toss flour, baking powder, and salt in a medium bowl.
With clean fingers or a pastry blender, rub or cut the lard into the flour until well combined (if using vegetable oil, mix it with the water and add them together).
Drizzle water over the top and stir until dough begins to clump together. Press the mixture together and knead it into a supple dough.
Divide the dough into 12 evenly-sized pieces. Roll each one into a ball and flatten it with your fingers. Cover the balls of dough with plastic wrap and let them rest for about 20 minutes.
In the meantime, heat a skillet or griddle over medium high heat (if you have an infrared thermometer, you're looking for around 400º F).
Using just enough flour to prevent sticking, roll rested dough into 6-inch circles with a rolling pin.
Cook tortillas on the preheated pan or griddle until they have deep golden brown spots on each side, about 30 seconds to 1 minute per side.
Cover finished tortillas with a clean towel or place them in a tortilla warmer until ready to serve.