01 - Combine olive oil, chili powder, smoked paprika, cumin, garlic powder, salt, pepper, and lime juice in a bowl. Add chicken and toss to coat thoroughly. Let marinate for at least 15 minutes, up to 2 hours for deeper flavor penetration.
02 - Rinse rice under cold water until water runs clear. Bring water to a boil in a saucepan, add rice and salt. Cover, reduce heat to low, and simmer for 15 minutes or until tender and liquid is absorbed. Fluff with a fork before serving.
03 - Heat a grill pan or skillet over medium-high heat. Cook marinated chicken for 5 to 6 minutes per side until fully cooked through, reaching an internal temperature of 165°F. Let rest for 5 minutes before slicing against the grain.
04 - Melt butter in a skillet over medium-high heat. Add corn kernels and cook until slightly charred, about 4 to 5 minutes. Remove from heat and stir in mayonnaise, sour cream, cotija cheese, minced garlic, chili powder, lime juice, salt, and pepper until well combined.
05 - Divide cooked rice evenly among 4 bowls. Arrange sliced grilled chicken, street corn mixture, diced avocado, cherry tomatoes, and fresh cilantro on top. Garnish with additional cotija cheese if desired and serve with lime wedges for squeezing.