I used to make this soup at a little café where I worked, and it was always received with a kind of surprised approval. People didn’t expect much from a cauliflower soup, and then it won them over. The rosemary fragrance and the deep caramelized flavor brings people around every time. This is also a great one to pair with my vegan butternut squash zuppa toscana if you’re feeding a crowd and want two very different soups on the table.
Five core ingredients, roasted until deeply nutty, then blended with good stock. That’s it! The potatoes combine with the cauliflower to give the soup a naturally creamy, hearty texture with no nuts, cream, or beans required.
The lemon juice goes in at the end, squeezed right over the hot vegetables before blending. It lifts everything and keeps the soup from tasting flat. Rosemary and the hot oven do the rest. That woodsy and warm flavor carries through every bite.
Because the ingredient list is so minimal, stock quality matters more here than in almost any other soup I make. A weak or watery stock will make a weak, bland soup. This is the one I’d pull out the homemade vegetable stock for.
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Creamy Roasted Cauliflower Soup with Potatoes
Ingredients
Soup
- 1 large head cauliflower
- 1 lb yukon gold potatoes, scrubbed
- 2 medium yellow onions, papery skin removed
- 2 tablespoons fresh rosemary leaves
- 3 tablespoons olive oil
- 2 heads garlic, top ⅓ cut off
- salt and ground black pepper, to taste
- 1 tablespoon fresh lemon juice, plus more to taste
- 5-6 cups vegetable stock
To Serve (optional)
- more olive oil
- croutons
- toasted and chopped nuts
- chopped leafy herbs
- balsamic reduction
- squeezes of lemon
- more ground black pepper
Equipment
- Blender
Notes
- Give the vegetables real space on the baking sheet — crowding is the most common reason this soup falls flat. Use two baking sheets if you need to. You’re looking for deep golden brown color on the vegetables; not just a light toast.
- With only five core ingredients, the stock is doing a lot of heavy lifting. A well-seasoned homemade stock makes a noticeable difference in this soup.
Instructions
- Preheat the oven to 400°F.
- Remove the core from the cauliflower and chop it into rough florets. Place the florets onto a large baking sheet.
- Chop the potatoes into pieces about half the size of the cauliflower florets and toss them onto the baking sheet as well.
- Chop the onions into rough 1-2 inch pieces and toss them onto the baking sheet. It doesn't matter if the onion layers stick to each other.
- Sprinkle the rosemary leaves over the vegetables. Liberally salt the vegetables and season with pepper to taste. Add the oil and toss the vegetables until evenly coated with the oil, rosemary, and seasoning.
- Place the garlic heads in a piece of foil. Drizzle the tops with olive oil and then wrap the foil tightly around the head. Nestle the garlic foil packet amongst the veg on the baking sheet.
- Roast vegetables for about an hour, flipping and tossing them here and there with a spatula/spoon to promote even browning. You should have deep caramelization.
- When done, remove the from the oven and set aside the garlic foil packet. Pour the lemon juice over the hot vegetables (I just drop the lemon half into the warm pan when I'm done so that it can release some oil too). Using your spatula, toss the vegetables with the lemon juice, scraping the browned bits off the bottom.
- Once the vegetables are cool enough for you to handle, add a portion of them to an upright blender along with some vegetable stock. Remove the roasted garlic from the foil and squeeze all of the roasted cloves into the blender as well. Keep doing this in batches until you've blended everything up.
- Transfer the blended soup to a large pot. Heat the large pot over medium heat until it comes to a boil. Add more stock or water to thin the soup if necessary and adjust seasoning to taste (more lemon, salt, pepper etc–I almost always add more of each). Serve hot with optional garnishes.
I was sceptical about this one but it’s actually really good. I enjoyed the caramelised flavour and adding white pepper gives it a lovely warmth. Would make again!
Delicious! Perfect food prep soup for fall lunches. Excellent flavor; my house smelled like fall all day! I topped it with sea salt roasted chickpeas for a nice mild crunch. Even my carnivore husband approved.
This recipe is delicious! One time, I roasted garlic along side everything else and puréed it too and it was great. I ignore the salting instructions, I sprinkle salt before roasting and I use full salt veggie broth. Having some extra roasted cauliflower and onions to sprinkle on top is always very nice.
I made this soup yesterday as part of a diner I was having for a friend. I was very excited about it because I love roasted cauliflower, but unfortunately, the soup was not flavorful. I followed the directions exactly. I’m sad to say that the end result was pretty bland, IMO. I had to add a few more seasonings and a couple of dashes of tabasco sauce to give it any kind of flavor. : (
So delicious! We were able to eat it for several meals. It has been very cold in Michigan and this soup was a wonderful comfort food after work and for lunches.
Very good! Pretty easy to make. Added a little coconut milk at the end to bump up the creaminess and added some roasted sunchokes on top. So good!
Wicked good! We made this last night but we added carrots. After everything was roasted we threw around half in the pot with veg stock and pureed it then added the rest of the veg. Then we took a big bunch of spinach and some pine nuts left over from pesto and put them on the baking sheet with the left over v.o.o. and roasted that as well to put on top. We will be making this again with two heads of cauli, and a couple more carrots. Thank you!
I dont usually get excited about soup but wow this recipe was so yummy and cosy and filling and I can’t wait to make it again!
What a delicious soup! It’s very easy to put together and the results are filling and warming. I’ll be making this again for sure.