ready in 1 hr 50 min.
In a large bowl, combine the flour, baking powder and salt. Cut in the shortening until the mixture is crumbly. If necessary, add additional shortening, 1 tablespoon at a time until the flour has been completely incorporated and the mixture is crumbly, but not dry. Mix in the hot water.
Knead the mixture, making sure to roll against the sides of the bowl to collect all dough. If the dough is sticking to the sides, add more flour 1 tablespoon at a time, until you can knead the dough into a soft round shape. Cover the bowl with a clean dish towel, and let it rest for about an hour.
Divide the dough into 10 to 12 smaller balls. Lightly flour a clean working surface. Roll each ball with a rolling pin to about 1/8 inch thickness.
Place each tortilla on a hot cast iron skillet over medium heat. Cook for about 1 to 2 minutes on each side, until no longer doughy.