Warming the tortillas helps them hold up to filling and rolling. To warm up tortillas in the microwave, place tortillas on a plate with a damp paper towel on top of each tortilla. Microwave on high for 20 seconds, or until the tortillas are warm. To warm up tortillas in the oven, preheat the oven to 350 degrees Fahrenheit. Wrap the tortillas in aluminum foil and transfer them to the oven. Bake for 10 minutes, or until heated through.