As I discuss in my Cream of Anything Soup mother dish article, sometimes you want to add some caramelization notes by roasting or pan searing the vegetable first. Other times you want the vegetable’s original flavor to shine through. Cauliflower and Broccoli are first cousins. They are different varieties of the same species (Brassica oleracea var. botrytis and Brassica oleracea var. italica, respectively). But I usually treat them differently in a cream of anything soup. Cauliflower needs some caramelization to bring out its flavor. Roasting brings out cauliflower’s awesomeness. I want that awesomeness in the soup, so I roast the cauliflower first. I really like roasted broccoli as well, but broccoli blanched simply in salted water is also delicious. For broccoli in a soup, I want the clean, unadulterated broccoli flavor to come through.

Anyway, we’re talking about Cream of Roasted Cauliflower Soup here. The recipe is quite simple, especially if you’ve had the practice of any cream of other things soup. Set the oven to 425°F. Cut up a head of cauliflower so that the florets are sliced in half. This will give them a nice flat surface to contact the baking sheet where most of the browning happens. Optionally slice out a bunch of tiny florets to roast to a crispy brown and use them as garnish on top of the soup! Toss the cauliflower with a couple tablespoons of olive oil and a good pinch of salt, and lay them out on the baking tray, cut side surface down. Put them in the oven and let them roast for 30 minutes. Let them go a little longer if they haven’t developed a nice caramelization on the cut side down. As the cauliflower approaches readiness, dice a medium onion and sauté in olive oil and a pinch of salt in a soup pot. Once the onions are soft and translucent, add a few cloves of minced garlic and sauté another minute. Add the roasted cauliflower to the pot and add enough stock (vegetable or chicken) to reach the top of the other ingredients (about a quart). You don’t have to simmer too long because the cauliflower was already cooked but simmering for longer is good. Puree the soup either with an immersion blender or a countertop blender. I prefer the immersion blender for convenience and easy cleanup. Take your time and you can make the soup quite smooth. Be careful if you go the countertop blender route, as steam in a vortex can literally be explosive. Work in batches, hold the top in place with a kitchen towel to protect your hand, and slowly bring the blender to full speed with each batch. Once pureed, give the soup a taste test. If it needs more salt, stir in a bit more salt. If you would like to improve its creamy mouthfeel, stir in an ounce or two of heavy cream. If it tastes a little muted, add a little acid. A teaspoon of vinegar, or a vinegar-based sauce such as Texas Pete’s or Worcestershire are options. When the taste is there, go ahead and serve.  

While the ingredients are different, the photo walk through for the Cream of Winter Squash recipe can provide visual guidance. For ideas to garnish the soup, I have lots of ideas listed in the Cream of Anything Soup mother dish write up.