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