In a bowl, mix the mayonnaise, sour cream, lime juice, and cayenne pepper (if using) to create a creamy sauce. Set aside.
Season the chicken breasts with olive oil, chili powder, garlic powder, cumin, salt, and pepper.
Heat a skillet over medium-high heat and cook the seasoned chicken for about 6-7 minutes on each side, or until fully cooked and no longer pink in the center. Remove from heat and let it rest for a few minutes before slicing.
In the same skillet, add the corn and cook for 3-4 minutes until heated through and slightly charred.
To assemble the bowls, start with a base of cooked rice, then top with sliced chicken, charred corn, and drizzle the creamy sauce over the top.
Finish with crumbled feta cheese and chopped cilantro. Serve immediately.