In a small mixing bowl whisk together olive oil, basil, garlic, and lemon juice and season with salt and pepper (about ½ tsp of each). Using the back of a spoon, press basil against sides and bottom of bowl (to help extract flavor from basil). Place chicken in a resealable bag and pound thicker parts of chicken to even thickness with a meat mallet, then pour basil mixture over chicken and evenly distribute basil over chicken. Seal bag while pressing excess air out, rub marinade over chicken and transfer to refrigerator and marinate 2 - 5 hours.
Preheat a grill to 425 - 450 degrees over medium high heat. Brush grill grates lightly with olive oil then place chicken on grill. Grill until cooked through, rotating once halfway through cooking, about 4 - 5 minutes per side (chicken should register 165 degrees in center of chicken on an instant read thermometer). Transfer to a cutting board and let rest 10 minutes then slice into strips or dice into cubes.
Whisk together all ingredients until well blended and season with salt and pepper to taste. Store in refrigerator until ready to use, stir again before pouring over salad.
In a large salad bowl gently toss together lettuce, peaches, corn, pecans, onions, and grilled chicken. Sprinkle goat cheese over top and drizzle with vinaigrette. Serve immediately after adding dressing.
