Also, I recently had white corn tortillas with fajitas at one of my favorite mexican restaurants. And I really, really loved the flavor, texture, and healthier option. I usually use flour tortillas with this marinade--but the white corn tortillas were amazing, as well.
Fajita Marinade from Betty Crocker's Cookbook
1/4 C vegetable oil
1/4 C red wine vinegar
1 teaspoon sugar
1 teaspoon dried oregano leaves
1 teaspoon chili powder
1/2 teaspoon garlic powder
1/2 teaspoon salt
1/4 teaspoon pepper
Mix all the ingredients in a resealable plastic food-storage bag. Add about 1 pound of boneless (you can also do 2-3 lbs bone-in beef or pork) chicken. Seal bag and refrigerate at least 4 hours (turning meat occasionally)--but no longer than 24 hours.
Add your favorite toppings and enjoy!