Corn tortillas are delicious, but if yours are a little stale, revive them with a quick dip in cold water before reheating them in a skillet or wok. They come back to life in seconds, and you get warm, fluffy tortillas perfect for wrapping or filling.
The video above is old, but a good demonstration of the method. Give each tortilla a quick dip in cold water right before you lay it on a non-stick skillet for about 30 seconds to heat up. Flip the tortilla just when it's warmed through on one side, and cook on the other for another few seconds. Stack them on a towel to trap the steam and heat the tortillas all the way through while still keeping them moist. Quick, easy, and simple.
The Right Way to Warm Corn Tortillas [Serious Eats (YouTube)]