In a small bowl, whisk together the chili powder, cumin, garlic powder, salt, and black pepper.
Place the chicken strips in a bowl and toss with 1 tablespoon of olive oil and half of the spice mixture.
Heat the remaining 1 tablespoon of olive oil in a large skillet over medium-high heat.
Add the chicken to the skillet and cook for 6 to 8 minutes until browned and cooked through, then remove from the pan and set aside.
Add the sliced onions and bell peppers to the same skillet and sprinkle with the remaining spice mixture.
Sauté the vegetables for 5 to 7 minutes until they are tender-crisp and slightly charred.
Return the chicken to the skillet and toss with the vegetables to combine and reheat.
Warm the tortillas in a dry skillet or microwave.
Assemble tacos by placing the chicken and vegetable mixture into tortillas, garnished with cilantro and lime wedges.