Begin by slicing the chicken breast into bite-sized pieces.
In a large skillet, heat the olive oil over medium-high heat.
Add the chicken pieces to the pan and season with chili powder, cumin, garlic powder, salt, and black pepper. Cook until the chicken is golden brown and cooked through, about 5-7 minutes.
While the chicken is cooking, gather the cooked brown rice, black beans, corn, cherry tomatoes, avocado, and lettuce in a mixing bowl.
Once the chicken is ready, remove it from the skillet and add it to the mixing bowl with the other ingredients. Toss gently to combine.
To assemble each bowl, start with a base of the chicken and vegetable mixture. Top with shredded cheese, salsa, and fresh cilantro if desired.
Serve immediately and enjoy your Chicken Taco Bowl!