Marinating the beef and vegetables in the lime-chili powder mixture gives these fajitas a Southwestern flavor.
Flour tortillas are available in many different sizes. To make a larger quantity of smaller fajitas, use 6 or 8-inch tortillas.
A traditional accompaniment to fajitas is guacamole, a mixture of mashed avocado, minced chiles and lime juice. Minced garlic and finely chopped tomato, onion and cilantro also may be added to guacamole.