Dice the chicken breast into bite-sized pieces and season evenly with chili powder, cumin, garlic powder, sea salt, and black pepper.
Heat the olive oil in a medium skillet over medium-high heat.
Add the diced red onion and bell pepper to the skillet, sautéing for 3-4 minutes until the vegetables are slightly softened and fragrant.
Add the seasoned chicken to the skillet and cook for 5-7 minutes, stirring occasionally, until the chicken is golden brown and cooked through.
Warm the pre-cooked brown rice and black beans in a small pot or microwave until heated through.
Assemble the bowl by placing the rice and beans at the base, then topping with the sautéed chicken and vegetable mixture.
Garnish the bowl with fresh avocado slices, chunky salsa, chopped cilantro, and a squeeze of fresh lime juice before serving.