6 cups vegetable or chicken broth (divided)
1/2 cup grated yellow onion
2 packages Earthbound Farm Frozen Organic Broccoli Florets
1 package Earthbound Farm Frozen Organic Rainbow Chard
  Juice of 1/2 lemon
  Salt and freshly ground black pepper (to taste)
1/4 cup nonfat Greek yogurt (as garnish, optional)
  Toasted croutons (as garnish, optional)