In a small bowl add chicken cilantro, garlic, olive oil, lime, salt and pepper. Marinade for 20 minutes in refrigerator. Place corn on grill and cook until slightly charred. Remove the kernels from the corn by holding the stem end of the husked ear of corn and rest the tip of the ear on the bottom of a very large bowl. Use a sharp paring knife to cut off corn kernels and let them fall into the bowl.
Cook chicken breast on grill for 3 to 5 minutes on each side until cooked throughout. Allow to rest, and cut chicken breast into pieces.
Begin assembling the layers of salad on half of the plate against the rim. Fill the rest of the plate with shredded lettuce. Top with rows of radish, next to that a row of tomato, then corn, then black beans, then cheese.
On the center and top place sliced chicken and avocados. Garnish with cilantro and onion.