In a small bowl, combine chili powder, cumin, paprika, garlic powder, onion powder, oregano, salt, and pepper. Set aside.
Heat 1 tablespoon of olive oil in a cast-iron skillet over medium heat. Once the oil is hot, add the sliced bell peppers and onion. Sauté for 5-7 minutes until the veggies soften and the edges start to char.
Stir in minced garlic and half of the seasoning mix (about 1 ½ tablespoons). Sauté for another 2-3 minutes, stirring frequently. If the pan becomes too dry, add a splash of water to prevent burning.
Once the vegetables reach your desired doneness, transfer them to a plate and set aside.
Wipe the skillet clean if needed, then heat the remaining tablespoon of olive oil. Add the chicken strips, the rest of the seasoning mix, and lime juice. Cook for 5-6 minutes, stirring occasionally, until the chicken is fully cooked and golden brown.
Return the veggies to the skillet and toss everything together. Cook for 1-2 minutes to reheat the vegetables and let the flavors meld.
Serve the chicken and veggies in warm tortillas. Top with salsa, guacamole, Greek yogurt, or your favorite toppings.