In a large skillet, heat the olive oil over medium heat. Season the chicken breasts with chili powder, cumin, garlic powder, salt, and pepper. Add the chicken to the skillet and cook for about 6-7 minutes on each side, or until fully cooked and no longer pink in the center. Remove from heat and let rest for a few minutes before slicing.
In the same skillet, add the corn and cook for 3-4 minutes until heated through. If using fresh corn, cook until slightly charred.
In a small bowl, mix together the mayonnaise, feta cheese, cilantro, lime juice, and cayenne pepper (if using). This will be your creamy dressing.
To assemble the bowls, start with a base of cooked rice. Top with sliced chicken, corn, avocado, and diced red onion. Drizzle with the creamy dressing.
Serve immediately and enjoy your delicious Mexican Street Corn Chicken Rice Bowl!