For this easy cauliflower soup recipe, we roast a whole head of cauliflower until golden brown and then blend it with onion, parmesan cheese, and broth until silky smooth. This healthy soup is creamy, decadent, and delicious!
We love cauliflower. It’s so versatile! This roasted cauliflower soup recipe is close to my heart. It’s rich and creamy (without cream), super simple, and tastes incredible.
We have so many cauliflower recipes on Inspired Taste, and honestly, I love them all, but this soup is the one I go to when I need a little comfort. A big bowl of this soup makes the day melt away. It’s the best!
Key Ingredients
- Cauliflower: I use one large head of cauliflower for this soup, which means you’ll get 4 generous servings.
- Garlic and Thyme: Since I roast the cauliflower for this soup, I take the opportunity to toss a few garlic cloves and fresh thyme onto the baking sheet. They add so much flavor!
- Onion and Celery: Once the cauliflower has finished roasting in the oven, we cook onion and celery with a pinch of red pepper flakes and salt, adding more nutritious vegetables to the soup and flavor.
- Broth: I love using a light broth so that the cauliflower shines. I especially love this easy chicken broth and this delicious veggie broth.
- Butter: I don’t add cream to this cauliflower soup, but I do add butter. Use a good-quality European-style butter or your favorite plant-based butter.
- Lemon Juice: A squeeze of fresh lemon juice brings this soup together. We highly recommend it.
- Cheese: I love adding parmesan cheese, but you can substitute it for another kind of cheese or leave it out altogether.
How to Make Roasted Cauliflower Soup
This cauliflower soup starts with roasting a whole head of cauliflower. I don’t pay too much attention to how well I chop the cauliflower. Slicing it into cauliflower steaks or slabs is the quickest way. Then we toss them with olive oil, salt, thyme, and whole garlic cloves (you can leave the peel on for now). As the garlic roasts in the oven, it softens and becomes sweet (like in our whole roasted garlic recipe)
The cauliflower and garlic roast in a hot oven for 20 to 25 minutes, so it’s pretty quick. When it is nearly finished roasting, you can prepare the remaining ingredients.
Just as the cauliflower is finishing in the oven, in a soup pot, cook roughly chopped onion and celery in butter (or olive oil) until soft. Then, pour in broth and add the roasted cauliflower. I have two favorite homemade broths for this: veggie broth or chicken broth.
The garlic will have softened tremendously. You can easily squeeze the soft garlic cloves to add the roasted garlic flesh to the pot.
Let the soup simmer for 10 minutes, then blend it into a smooth, decadent soup. I love adding some fresh lemon juice and parmesan cheese, but you can adjust the seasoning with fresh herbs, another kind of cheese, or leave it plain. You can see from the photos that the cauliflower soup is super creamy. It’s so creamy without the addition of heavy cream! We love it so much.
Easy Roasted Cauliflower Soup
- PREP
- COOK
- TOTAL
For this easy cauliflower soup recipe, we roast a whole head of cauliflower until golden brown and then blend it with onion, parmesan cheese, and broth until silky smooth. This healthy soup is creamy, decadent, and delicious! For more crunch, try serving this soup topped with our homemade garlic croutons.
Watch Us Make the Recipe
You Will Need
1 large head cauliflower, about 2 pounds
4 tablespoons olive oil
1 teaspoon fresh thyme leaves or 1/4 teaspoon dried thyme
4 garlic cloves, left unpeeled
1/2 large onion, chopped, about 1 ¼ cups
1 celery stalk, chopped, about 1/2 cup
Pinch crushed red pepper flakes, optional for heat
4 cups (946ml) vegetable broth or chicken broth
2 tablespoons butter
1 tablespoon fresh lemon juice, or more if needed
1/4 cup grated parmesan cheese, plus more for serving, optional (1/2 ounce)
Directions
1Preheat the oven to 425°F (220°C) and prepare a baking sheet. We roast the cauliflower directly on the baking sheet, but for easy cleanup, line it with parchment paper or a silicone baking mat.
2Remove the larger leaves from the cauliflower and leave the core intact. (You can save the leaves to blend into the soup later.)
3Slice the cauliflower in half and cut it into 3/4-inch thick slices.
Drizzle two tablespoons of olive oil onto the baking sheet, then arrange the cauliflower on top of the oil.
4Add the unpeeled garlic cloves (they will roast in their peels) and the thyme, then drizzle over two more tablespoons of olive oil. Move the cauliflower slices around so they each have a chance to touch some oil.
5Roast for 20 minutes or until the bottom of each slice looks well browned. Flip each piece, and then roast for 5 minutes more.
6Melt two tablespoons of butter in a deep soup pot over medium heat. Then, stir in the onions, celery, pinch of red pepper flakes, and 1/4 teaspoon salt. Cook until softened, about 5 minutes.
7When they are cool enough to handle, squeeze the garlic from inside each clove and place it in the soup pot. Discard the garlic peel.
8Transfer the roasted cauliflower to the pot and pour in the broth. If you saved any cauliflower leaves from earlier, add them to the pot. Bring to a simmer and cook for 10 minutes.
9Turn off the heat, and add the cheese and two tablespoons of lemon juice.
10Blend the soup until smooth. An immersion blender is the easiest, or you can use a blender. If you use a regular blender, it is best to blend in batches and fill the blender less than you usually would since the soup is so hot. We like to remove the lid’s center insert and cover it with a kitchen towel while blending. This helps to release some of the steam and prevents the blender lid from popping off (which can be a big, hot mess).
11Taste the soup and add more lemon juice, salt, and pepper until the flavor pops (it should make you smile). Serve with more cheese, a few grinds of black pepper, and a drizzle of olive oil on top.
Adam and Joanne's Tips
- Storing: This cauliflower soup lasts in your refrigerator for up to 5 days. It can also be frozen for up to one month, probably longer.
- Soup is too thick: Add 1/4 cup to 1 cup of water. Add enough water to achieve your preferred thickness. The water will not water down the flavor of your soup, but if you are concerned or have more on hand, you can use stock or broth.
- Vegetarian adaptations: Use vegetable broth, a vegetarian-friendly cheese or leave it out altogether.
- Vegan adaptations: Use vegan broth, vegan butter and vegan cheese or a couple tablespoons of nutritional yeast instead (my preference).
- The nutrition facts provided below are estimates.
This soup is delicious! I didn’t have quite enough cauliflower so I added a large russet potato with the cauliflower and garlic. I’ll be making this again!
We loved this soup! It was easy to prepare and was creamy without adding milk or cream. The lemon juice brightened the flavor and really put it over the top. Do not skip that ingredient. I will definitely make this again.
Loved this recipe! I did not add crushed red peppers but added smoked paprika instead for a fuller flavor. Because I used unsalted veggie broth, I did need to add salt at the end to help bring out the zing of the paprika and lemon juice. YUMMY!! Will def make again!
Made this soup for the first time tonight: so easy and very very delicious.
Made this for the first time. I love roasted cauliflower (hubby is not a fan) It was good and easy to make. I did not use celery or red pepper flakes. Would definitely use the red pepper flakes next time
Nice short ingredient list of mostly items I already have (minus fresh cauli and parm) and easy to put together. This is a filling soup that feels guiltier than it is 😉 Great way to fill up without cream! If my husband liked it (he’s too picky) I would make it more often, but I’ll try another one your soup recipes before making this again.
I loved the cauliflower roasted, and not adding extra dairy..the Parmesan was perfect enough.
I felt full AND it was very tasty.
Awesome soup and very easy to make, wonder if it could be made with frozen cauliflower.
Hi Patricia, So happy you enjoyed it! You can use frozen cauliflower. I still recommend roasting it for flavor (either from frozen, which won’t brown as well) or thaw and then roast.
Wow, so delicious, I added extra parm and lemon, so yummy
I made this soup last night. It was incredibly easy to make and out of this world delicious! Thank you for sharing !
Yay! We are thrilled to hear that the soup was a hit 🙂
Made the roasted cauliflower soup this morning and YUM! I did not use celery as I did not have on hand and not a huge fan of cooked celery anyway. Instead of cheese, I sprinkled nutritional yeast on top before serving. Will definitely be making this recipe again. Thank you and keep cooking together! It’s very sweet.
We are thrilled that you enjoyed the soup, Terri! Thanks for sharing.