Sift together flour, salt and baking powder in a large bowl. Use your hands to incorporate the shortening until the mixture becomes crumbly. Pour in the warm water and mix with your hands till a slightly sticky dough ball forms.
Turn the dough out onto a lightly floured surface and knead for 5 minutes or until dough becomes smooth and elastic. Wrap in plastic wrap and let rest on the counter for 30 minutes.
Once it's rested, heat a large skillet on high for 5 minutes then reduce heat to medium. Divide dough into 16 even balls. Use a rolling pin to roll out dough into 1/4 inch thin circles and cook one at a time in the dry skillet for 30 seconds per side.
*Do not roll dough out more than once or the tortillas can become tough.
**Be sure to place cooked tortillas directly into a tortilla warmer, or wrap in a slightly damp & warm towel so the tortillas stay soft and pliable.
***Eat immediately or place uneaten tortillas in a zip close bag in the fridge. Reheat in microwave in the bag, then place in the tortilla warmer again.