Slice pork into strips and place them in a one quart zip-top bag. Add lime juice, 1 tablespoon olive oil, and spices to the bag, squish around to coat, then let it sit to marinate. (I was in a hurry, so just quick marinated mine while slicing the veggies -- but you can let yours go longer in the fridge for more flavor if you like, turning occasionally.)
While the pork marinates, cut up your veggies.
After pork marinates: Heat 1 tablespoon of olive oil in a 12" cast iron skillet on medium-high heat for about a minute. Swirl to coat the bottom of the pan, then add the pork and cook for just one minute, stirring constantly.
Add another tablespoon olive oil to the skillet. Stir the onion, garlic, sliced bell peppers, and spices in with the pork, then continue cooking over medium-high heat for another five minutes, stirring occasionally.
Squeeze in lime juice, stir, and continue to cook for another three minutes or until the pork is cooked through and veggies are tender to your liking.
Serve fajitas immediately in tortillas along with your favorite toppings (sour cream, diced tomato, shredded cheese, lime wedges, avocado, pico de gallo, black olives, shredded lettuce, salsa...).
Notes
My fajitas are shown here topped with leftover black beans & corn, chopped avocado, and diced garden tomatoes. Each option was good, but I especially recommend the tomato (or some pico de gallo) in order to add a fresh pop of juiciness!