In a medium bowl, whisk together 1 tablespoon olive oil, lime juice, chili powder, cumin, garlic powder, salt, and pepper.
Toss the chicken strips in the marinade and let sit for 10 minutes.
Heat the remaining 1 tablespoon olive oil in a large skillet over medium-high heat.
Add chicken to the skillet and cook until browned and cooked through, approximately 5-7 minutes. Remove chicken from skillet.
In the same skillet, add the bell peppers and onion. Sauté until tender-crisp and slightly charred, about 5 minutes.
Return chicken to the skillet and toss with the vegetables to combine and reheat.
Divide the cooked rice among four bowls.
Top rice with the chicken and vegetable mixture, black beans, avocado slices, and fresh cilantro.
Serve with a dollop of sour cream.