In a bowl, whisk together olive oil, lime juice, chili powder, cumin, garlic powder, smoked paprika, salt, and pepper. Add the chicken breasts, ensuring they are fully coated in the marinade. Cover and let sit for at least 30 minutes.

Rinse long-grain white rice under cold water until it runs clear to remove excess starch. In a saucepan, combine the rinsed rice and chicken broth, bringing it to a boil over medium heat. Cover and simmer for about 18-20 minutes, or until the rice is tender.

Preheat a grill or skillet over medium heat. Remove the marinated chicken and cook for 6-7 minutes on each side until it reaches 165°F (75°C). Allow the chicken to rest before slicing.

In serving bowls, add a generous portion of the rice as the base. Top with black beans, corn, diced tomatoes, and sliced chicken. Sprinkle fresh cilantro on top.

Add avocado slices, shredded cheese, and sour cream on each serving. Serve with lime wedges on the side.