In a mixing bowl, combine olive oil, lime juice, lime zest, chili powder, brown sugar, salt, ground cumin, smoked paprika, onion powder, garlic powder, and chipotle chili powder (if using). Whisk until smooth.

Pat chicken breasts dry and coat them evenly with the marinade. Let it sit for at least 30 minutes.

Cook chicken in a grill pan over medium-high heat for 5-7 minutes on each side until cooked through.

Let chicken rest for 5 minutes before slicing.

In a separate bowl, combine cherry tomatoes, corn, red onion, jalapeño, and cilantro. Add additional lime juice, salt, and pepper to taste.

Just before serving, gently fold in diced avocados into the salsa.

Slice the rested chicken and serve on a platter with avocado corn salsa on top.