In a large bowl, marinate the diced chicken breast with olive oil, chili powder, cumin, lime juice, salt, and pepper. Let it sit for 15 minutes.
While the chicken is marinating, heat a skillet over medium heat. Add the marinated chicken and sauté for about 6-8 minutes until fully cooked and golden brown. Remove from heat and set aside.
In individual serving bowls, layer the cooked brown rice as the base.
On top of the rice, evenly distribute the cooked chicken, black beans, corn, diced red bell pepper, and cherry tomatoes.
Add diced avocado and a sprinkle of shredded cheese over each bowl.
Finish with a sprinkle of fresh cilantro and an extra squeeze of lime juice on top.
Serve with optional toppings like sour cream, salsa, or jalapeños for added flavor.