Dice the chicken breast into small, uniform bite-sized pieces to ensure even cooking.
In a small bowl, toss the chicken with sea salt, black pepper, chili powder, and ground cumin until well coated.
Heat the olive oil in a skillet over medium-high heat until shimmering, then add the diced onion and red bell peppers.
Sauté the vegetables for 3-4 minutes until they are tender and slightly caramelized around the edges.
Add the seasoned chicken to the skillet, cooking for 6-8 minutes and stirring occasionally until the chicken is golden brown and cooked through.
In a serving bowl, combine the warm cooked brown rice and the black beans as the base.
Layer the sautéed chicken and pepper mixture over the rice and beans.
Top the bowl with fresh salsa, sliced avocado, and a garnish of fresh cilantro.
Finish with a bright squeeze of lime juice over the entire bowl before serving.