Creamy Cauliflower Soup Sans Cream (Dorie Greenspan) - cooking recipe

Ingredients

1 tablespoon olive oil
1 tablespoon unsalted butter
2 large onions, coarsely chopped, Vidalia, Spanish, or yellow (about 3/4 pound)
2 garlic cloves, split, germ removed, and thinly sliced
3 celery, stalks trimmed and thinly sliced
2 thyme, sprigs leaves only
salt and fresh ground white pepper
1 head cauliflower, leaves removed, broken into florets (discard the tough core)
6 cups vegetable broth or 6 cups chicken broth

Preparation

Put the olive oil and butter in a large Dutch oven or soup pot and warm over low heat. When the butter is melted, add the onions, garlic, celery, thyme, 1/2 teaspoon salt, and a few grinds of white pepper. Stir until all the ingredients glisten with oil and butter, then cover the pot and cook slowly, stirring often, for 20 minutes.
Toss the cauliflower into the pot and pour in the broth. Bring to a boil, reduce the heat so that the broth simmers gently, and cook, uncovered, for another 20 minutes, or until the cauliflower is very soft.
Puree the soup in batches in a blender or food processor; or use an immersion blender. This soup is best when it is very smooth, so if you think it needs it, push it through a strainer. (If you've used a standard blender, this shouldn't be necessary.) Taste for salt and pepper. Serve plain or garnished with the topping of your choice.