Add olive oil, garlic, chipotle powder, cumin, oregano, salt, and pepper to a large Ziploc bag.
Add chicken strips, peppers, and onion to the bag.
Seal, give it a shake to coat completely, and marinate in the fridge for at least 1 hour. You can do this ahead of time and leave it in the fridge until you are ready to cook dinner.
Preheat oven to 400° F. Line a baking sheet with aluminum foil. Spread the chicken and vegetables in a single layer on the pan.
Bake for 20 to 25 minutes, or until cooked through.
Serve on tortillas and add lettuce, cheese, cilantro, sour cream and salsa, or your desired toppings. Spritz with lime.