01 - Rinse rice under cold water until water runs clear. Combine rice, water, and salt in a saucepan. Bring to a boil, reduce heat, cover, and simmer for 15 minutes. Remove from heat, let stand covered for 5 minutes, then fluff with a fork.
02 - In a bowl, mix olive oil, chili powder, garlic powder, smoked paprika, cumin, salt, and pepper. Coat chicken thoroughly with the spice mixture. Grill or pan-sear over medium-high heat for 5 to 7 minutes per side until internal temperature reaches 165°F. Rest for 5 minutes before slicing.
03 - Heat 1 tbsp olive oil in a skillet over high heat. Add corn kernels and cook, stirring occasionally, until charred in spots (about 5 minutes). Remove from heat and cool slightly. In a bowl, whisk together mayonnaise, sour cream, garlic, lime juice, and chili powder. Fold in charred corn, cotija cheese, and chopped cilantro.
04 - Divide prepared rice among 4 serving bowls. Arrange sliced chicken over the rice, then top generously with street corn mixture. Add diced avocado, extra fresh cilantro, and lime wedges. Serve immediately while chicken is warm.