1. Preheat the grill to medium-high; lighhtly coat the grate with cooking oil. Whisk the oil with the vinegar, salt and garlic. Reserve 1/4 cup and set aside.
2. Brush some of the remaining dressing over both sides of each slice of bread. Toss the remaining with the chicken breasts.
3. Place the chicken and bread on the grill and immediately reduce the heat to medium. Cook the chicken for 5 to 7 minutes per side or until cooked through. Grill the bread for 3 minutes per side or until well-marked and toasted. Cool completely.
4. Chop the chicken and bread into bite-sized pieces. Toss with the tomatoes, basil, yellow pepper, onion, cucumber, olives and the reserved dressing. Let stand for 10 minutes before serving.
1. Panzanella is a great way to use up leftover bread.
2. Use a good quality olive oil for the best flavor.
3. Toss a handful of aromatic wood chips such as mesquite or hickory over the coals of your grill once they're fully lit. This will create a whole new dimension of flavor without adding extra calories.