Provided by: Chef Dan Barber
Preheat oven to 400 degrees.
Put the cauliflower in a large pot of boiling salted water, and blanch for 2 to 3 minutes, or until just tender when pierced. Drain the cauliflower, and set on a baking sheet. Roast in the oven for 20 minutes. Do not allow it to color.
Heat the oil in a large pot or sauté pan, add the onion and shallots, and sweat over very low heat until they start to break down, at least 20 minutes. Again, do not allow them to color. Add the roasted cauliflower to the pan, and season with salt and pepper. Sauté for 3 minutes, again making sure the vegetables don’t color. Add 2 cups of vegetable stock, and cook until all the liquid has evaporated. Stir in the grated horseradish and apple, and remove from the heat.
Heat the remaining vegetable stock in a saucepan. Put the cauliﬂower mixture into a blender along with a little hot stock, and purée, adding the remaining stock.
Return the soup to the pot, and place over low heat. Whisk in 1 teaspoon of the sherry vinegar, or more to taste. Season with salt and pepper. Serve immediately.(Published 2004)