In a large bowl add flour and shortening. Using your hands or a pastry blender, work the shortening into the flour until the mixture resembles wet sand.
Bring to boil a cup of water. Remove from heat and add salt, stir until the salt dissolves.
Stir in hot water to the dry ingredients until just combined. Turn out dough onto a lightly floured surface and knead until a smooth ball forms. About three minutes. Wrap dough in plastic a set aside to rest for a minimum of two hours. Do not refrigerate.
Separate the dough into small round balls. Roughly 1.5 ounces makes a nice size tortilla. Flatten the ball on a lightly floured surface and roll once, turn 1/4 turn and roll again, repeat a few more times and continue to roll out until paper thin. Roll out all the dough.
Heat a cast iron comal or griddle to medium heat. Splash a bit of water to check if the comal is at the proper temp. The water will sizzle and quickly evaporate when ready. Place a tortilla on the comal and cook until it just begins to bubble, flip and cook until light golden, flip to finish cooking.
Lay out the hot tortillas onto a clean kitchen cloth to cool flat. Stack the tortillas and store in a plastic bag. They will keep refrigerated for several days or frozen.