Zucchini and Basil Soup

I love Zucchini....grilled, sauteed, roasted, stuffed.... A client of my husbands gave us a beautiful big zucchini from their garden and I stared at it until I went cross eyed.  Well, not really but I did decide to make soup.  Unsure of what I would flavour it with, I also have an abundance of basil so it was a no brainer. 
This soup is easy, healthy, low in calories and fat, and has a simple fresh flavour with a little tang from the yogurt.  I'm quite addicted to it.  It'll keep well for few days in the fridge as well.  I've added a couple options for garnish and if I do say so myself, they're all good.
Tis the season for zucchini so make soup.
p.s. The basil was most flavorful the first day but lost a little of it's oomph by day 2, although the soup was still really, really good.  Garnish with a little fresh basil if you want the punch.

Zucchini and Basil Soup

Serves 4

2 lbs Zucchini, sliced and cut into chunks
1/4 cup sweet onion, chopped
3 cloves of garlic, chopped
4 cups low sodium chicken broth
3/4 cups water
1/2 tsp salt, or to taste
fresh pepper
2 tbsp fresh parsley
12-15 Basil leaves
3-4 tbsp full fat plain Greek Yogurt
Drizzle olive oil for garnish (optional)
Fresh grated Parmesan for garnish (optional)
Goat Cheese for garnish (optional)
Chili Flakes for garnish (optional)

Bring the chicken broth and water to a boil in a large pot, carefully add the zucchini, onion and garlic.  Simmer on medium high for about 20 minutes or until the vegetables are soft.  Add the parsley and salt and pepper.  Let the soup cool a little before blending to prevent scalding and splattering hot soup.  Once slightly cooled puree in batches adding the basil to the blender.  During the last batch, add in the greek yogurt and blend until smooth.  Place back in the pot to gently re-heat.