Coat a mixing basin with 2 teaspoons of oil, 2 tablespoons of lime juice, and all the ingredients (pepper, chili powder, cumin, paprika, onion powder, garlic powder, salt, and pepper). Thoroughly combine.
In the meantime, cut the chicken breasts lengthwise and add the cutlets to the marinade, turning them over to coat them evenly.
While you prepare the remaining vegetables, set that aside. Let it marinate for no more than four hours.
Cut the bell peppers and onions into 1/4-inch pieces by slicing them thinly with the knife’s grain.
On medium heat, warm a big, heavy skillet (made of cast iron or another material). Fry the chicken in a single layer in 1 tablespoon of oil for 3 to 5 minutes per side, or until it becomes golden and a meat thermometer registers 165˚F when checked in the middle. Cook until done.
Prepare in smaller batches if needed. While the veggies are cooking, lay the chicken out on a chopping board to rest.
In the same skillet, sauté the bell peppers and onion with 1 tablespoon of oil over medium heat until they soften and are slightly browned, stirring regularly for about 5 to 6 minutes. Season with salt and pepper to taste.
Meanwhile, while the veggies are cooking, thinly slice the chicken against the grain.
After the veggies are done, add the chicken back to the pan, stir to combine, and then remove from the heat.
Combine with tortillas that have been warmed, top with cilantro, and squeeze over fresh lime juice.