In a bowl, mix the chili powder, garlic powder, cumin, salt, and pepper. Rub this spice mixture all over the chicken breasts.

Heat 1 tablespoon of olive oil in a large skillet over medium-high heat. Add the seasoned chicken and cook for about 6-7 minutes on each side, or until cooked through and no longer pink in the center. Remove from the skillet and let rest for a few minutes before slicing.

In the same skillet, add the remaining tablespoon of olive oil and the corn. Sauté for about 5 minutes, or until the corn is heated through and slightly charred. Remove from heat.

In a small bowl, combine the mayonnaise, sour cream, lime juice, and half of the Cotija cheese. Mix well to create the sauce.

To assemble the bowls, start with a base of cooked rice, then top with sliced chicken, sautéed corn, and a drizzle of the sauce. Sprinkle with the remaining Cotija cheese and chopped cilantro. Add avocado slices if desired.