Preheat broiler to high. In a small cup, combine limejuice, chili powder and salt. Brush corn ears with the seasoning mixture; place on a broiler pan. Broil 6 inches from heat source until lightly browned; turn and continue broiling until barely cooked, a total of 7 to 10 minutes. Cool.
Meanwhile, in a bowl, combine, chicken, tomatoes and radishes. Cut each avocado into slices then cut slices in half crosswise; add to chicken mixture. Add 1/4 cup Spicy Salad Dressing; toss gently.
Cut two or three 1/4-inch slices from each corn ear; set aside. Cut remaining corn kernels from the cobs, by holding the ear upright in a shallow bowl so the kernels don’t scatter. Divide salad greens among 4 dinner plates.
Top with the chicken mixture then corn kernels. Garnish with reserved corn rounds. Serve with additional dressing, if desired. Spicy Salad Dressing: To 1/2 cup of your favorite vinaigrette dressing, add 1 teaspoon chili powder, and 1/8 teaspoon each ground cumin and ground red pepper (cayenne).