Step 1

Just before serving: to a large bowl, add the spinach, fresh blueberries, onion, feta cheese, and chopped walnuts (if using).

Step 2

Gently toss to combine, add salad dressing, and toss again. Serve immediately. Note: if storing for later, keep the salad in the refrigerator and add the walnuts and dressing just before serving, as the walnuts will soften up if refrigerated and the dressing will wilt the spinach.