Easy Roasted Cauliflower Soup
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! Jump to the Roasted Cauliflower Soup Recipe
How to Make Our Favorite Cauliflower Soup
Both Adam and I love this roasted cauliflower soup. It’s surprisingly easy and tastes much richer and decadent than you’d think, given that we don’t add cream. If you are looking for more ways to cook cauliflower, take a look at our Garlic Herb Cauliflower Rice or these Roasted Cauliflower Tacos.
The soup starts with roasting a whole head of cauliflower. We don’t pay too much attention to how well we chop the cauliflower and aim for similar-sized pieces. Then we toss with olive oil, thyme, and whole garlic cloves — you can leave the peel on for now.
Roast the cauliflower in a hot oven until golden. This takes around 20 minutes, so it’s pretty quick. We love roasting cauliflower, here’s our Chili Lime Roasted Cauliflower.
When it is nearly finished roasting, you can prepare the remaining ingredients. In a soup pot, cook roughly chopped onion and celery in butter until soft. Then, pour in broth and add the roasted cauliflower.
The garlic will have softened tremendously. You can easily squeeze the soft garlic cloves so the roasted garlic flesh can be added to the pot. If you love roasted garlic, here’s how we roast whole heads of garlic.
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 our roasted cauliflower soup is super creamy. It’s so creamy without the addition of heavy cream! We love it so much.
More Delicious Cauliflower Recipes
- Chili Lime Roasted Cauliflower
- Spicy Roasted Cauliflower Burritos
- Herby Cauliflower Salad with Chickpeas
- Chimichurri Cauliflower Steaks
- Baked Buffalo Cauliflower Wings
- Mashed Cauliflower
Easy Roasted Cauliflower Soup
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!
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 stalk celery, chopped, about 1/2 cup
Pinch crushed red pepper flakes, optional for heat
2 tablespoons unsalted butter or vegan butter
1 tablespoon fresh lemon juice, or more if needed
1/4 cup grated parmesan or cheddar cheese, plus more for serving, optional
- Roast Cauliflower and Garlic
- Make Soup
Heat the oven to 425° Fahrenheit 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.
Remove the larger leaves from the cauliflower, and leave the core intact. (You can save the leaves for blending into the soup later).
Slice 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.
Add the unpeeled garlic cloves (they will roast in their peels), then drizzle over two more tablespoons of olive oil. Move the cauliflower slices around, so they each have a chance to touch some oil.
Roast for 20 minutes or until the bottom of each slice looks well browned. Flip each piece, and then roast for 5 minutes more.
Melt 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.
When they are cool enough to handle, squeeze the garlic from inside each garlic clove, and place them into the soup pot. Discard the garlic peel.
Transfer the roasted cauliflower to the pot, and then 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.
Turn off the heat, and add the cheese and two tablespoons of lemon juice.
Blend 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 not fill the blender as much as 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).
If the 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.
Taste the soup, and then 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
- 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).
- Nutrition facts: The nutrition facts provided below are estimates. We have used the USDA database to calculate approximate values.