Preheat grill or indoor grill pan (even a regular ol' skillet will work too), over MED heat.
Season chicken breasts as desired, then place on grill and cook about 4-5 minutes per side (or until juices run clear and chicken is cooked through and golden).
Set chicken aside to rest.
While chicken is cooking, whisk together vinaigrette ingredients in a small mixing bowl. Set aside.
While chicken is resting, add walnuts to a small DRY skillet and toast over LOW heat for several minutes, or until nuts are fragrant and slightly toasted.
Add spinach to a serving bowl, then top with shallots, apples, strawberries, walnuts, and blue cheese.
Slice (or dice) chicken, and place on top of the salad.
Drizzle with vinaigrette as desired, and enjoy!