Whisk together all ingredients for the syrup in a medium bowl.
For the salad, divide the spring mix between 4 bowls or plates. Top with all remaining salad ingredients.
Drizzle the syrup on top of the salads and serve immediately.
Notes
Balsamic Syrup: If you're pressed for time, you can buy balsamic glaze instead of making this syrup. Or just go with a good balsamic vinaigrette.
Chicken: You don't have to grill chicken to make this salad! You can use just about any leftover chicken you have on hand, or pick up a rotisserie chicken.
Customize It: The point of this salad is to use fresh, local summertime produce, so use what you like and/or what's available in your area.