In a small bowl, combine chili powder, cumin, paprika, garlic powder, onion powder, salt, and pepper.
Toss chicken strips with half of the spice blend and one tablespoon of olive oil.
Heat a large cast-iron skillet over medium-high heat.
Add chicken to the skillet and cook until browned and internal temperature reaches 165 degrees Fahrenheit, approximately 6 to 8 minutes.
Remove chicken from the skillet and set aside.
Add the remaining tablespoon of olive oil to the same skillet.
Add bell peppers and onions and sauté until tender-crisp, approximately 5 minutes.
Stir in the remaining spice blend to the vegetables.
Return the chicken to the skillet, drizzle with lime juice, and toss to combine.
Serve warm with whole wheat tortillas.