Marinate the chicken: In a bowl, mix olive oil, chili powder, cumin, smoked paprika, garlic powder, salt, pepper, and lime juice. Coat the chicken and let sit 15–30 minutes (or up to 8 hours in the fridge).
Cook your base: Prepare rice or quinoa according to package directions. Fluff and keep warm, or chill if you prefer a cold bowl.
Char the corn: Heat a large skillet over medium-high.
Add corn (no oil needed if using a good nonstick). Let it sit to get some color, then stir. Cook 5–7 minutes until lightly charred.
Season with a pinch of salt.
Make the sauce: Stir together Greek yogurt, mayo (if using), lime juice, minced garlic, chili powder, and salt. Taste and adjust lime or salt.
Cook the chicken: Grill or pan-sear over medium-high heat, 4–6 minutes per side for breasts (thighs may need a bit longer), until cooked through. Rest 5 minutes, then slice.
Assemble the bowls: Divide rice or greens into bowls.
Top with chicken, charred corn, black beans, tomatoes, red onion, and avocado.
Add the finishing touches: Drizzle the yogurt-lime sauce over the top. Sprinkle cotija and cilantro. Add a squeeze of lime and a dash of hot sauce if you like heat.