Paul Bertolli's Cauliflower Soup

(Recipe from Food 52 blog)

3 Tbsp. olive oil 1 medium onion (6 oz.), sliced thin
1 head very fresh cauliflower (about 1 1/2 lbs.), broken into florets
salt, to taste
5 1/2 cups water, divided

Warm the olive oil in a heavy-bottomed pan. Sweat the onion in the oil over low heat, without letting it brown, for 15 minutes.

Add the cauliflower, salt to taste, and 1/2 cup water. Raise the heat slightly, cover the pot tightly, and stew the caulifower for 15 to 18 minutes, or until tender. Then add another 4 1/2 cups hot water, bring to a low simmer, and cook an additional 20 minutes uncovered.

Working in batches, puree the soup in a blender to a very smooth, creamy consistency. Let the soup stand for 20 minutes. In this time it will thicken slightly.

Thin the soup with 1/2 cup hot water, if needed. Reheat the soup. Serve hot, drizzled with a thin stream of olive oil and freshly ground pepper.

(Very simple and delicious. I used vegetable broth in place of water.)