Marinate the chicken: Slice the chicken breasts into thin strips. In a bowl, mix olive oil, lime juice, minced garlic, chili powder, cumin, paprika, salt, and black pepper. Add the chicken strips and coat well. Let it marinate for at least 15 minutes.

Prepare the vegetables: Slice the bell peppers and onion into thin strips. Set aside.

Cook the chicken: Heat a large skillet over medium-high heat. Add the marinated chicken and cook for 5-7 minutes until fully cooked. Remove from the skillet and set aside.

Cook the vegetables: In the same skillet, add a bit more olive oil if needed. Add the sliced bell peppers and onion. Cook for 5-6 minutes until they are tender but still crisp.

Combine and serve: Return the cooked chicken to the skillet with the vegetables. Stir well and cook for another 2 minutes. Warm the tortillas according to package instructions.

Assemble the fajitas: Serve the chicken and vegetable mixture on warm tortillas. Top with sour cream, shredded cheese, chopped cilantro, and a squeeze of lime juice.