Marinate the Steak:
In a large mixing bowl, combine olive oil, lime juice, soy sauce, cumin, chili powder, garlic, smoked paprika, salt, and pepper. Add the steak and coat thoroughly. Cover and marinate in the refrigerator for at least 30 minutes or up to 4 hours for maximum flavor.
Cook the Steak:
Heat a large skillet or grill pan over medium-high heat. Add 1 tablespoon of olive oil.
Remove the steak from the marinade, letting excess drip off. Cook the steak for 4–5 minutes per side for medium-rare, or to your desired doneness.
Transfer the steak to a cutting board and let it rest for 5 minutes before slicing thinly against the grain.
Sauté the Vegetables:
In the same skillet, add the remaining tablespoon of olive oil. Sauté the bell peppers and onions over medium heat for 5–7 minutes, until tender and slightly caramelized.
Assemble the Fajitas:
Warm the tortillas in a dry skillet or microwave.
Layer the sliced steak and sautéed vegetables onto the tortillas. Add your favorite toppings, fold, and serve.