In a large soup pot, saute the chopped onion in a few tablespoons of water or vegetable broth for 3-5 minutes, until translucent.
Add the garlic, carrots, celery and saute a few more minutes. Next add the cauliflower and vegetable broth.
Bring to a boil and cook for 10-15 minutes.
Now, use your immersion blender if you have one and blend a few times, until the soup is creamy but still has some texture. If you prefer, you can blend all the soup in a blender and then add in the greens.
Add salt, to taste (will depend on the saltiness of your vegetable broth).
Now add the chopped swiss chard to the pot and stir well.
Serve with brown rice if desired or a good loaf of bread and salad.