01 - Combine rice, water, and salt in a medium saucepan. Bring to a boil over high heat, then reduce heat to low, cover, and simmer for 15 minutes or until water is absorbed. Remove from heat and let stand, covered, for 5 minutes. Fluff with a fork before serving.
02 - Whisk together olive oil, chili powder, smoked paprika, garlic powder, cumin, salt, black pepper, and lime juice in a bowl. Add chicken breasts and turn to coat evenly. Let marinate at room temperature for at least 10 minutes.
03 - Preheat a grill pan or skillet over medium-high heat. Remove chicken from marinade and grill for 6-7 minutes per side, or until internal temperature reaches 165°F and juices run clear. Transfer to a cutting board and rest for 5 minutes before slicing into strips.
04 - Heat a skillet over medium-high heat. Add corn kernels and cook for 3-4 minutes, stirring occasionally, until lightly charred. Remove from heat and transfer to a mixing bowl. Add mayonnaise, sour cream, cotija cheese, chili powder, lime juice, cilantro, salt, and pepper. Stir until evenly combined.
05 - Divide cooked rice among three serving bowls. Arrange sliced chicken, street corn mixture, avocado slices, and diced red onion on top of each bowl. Garnish with additional cilantro and serve with lime wedges on the side.