This roasted cauliflower soup is proof that a humble vegetable can taste luxurious. Roasting turns the florets golden and nutty, and when they are blended with garlic and broth the soup becomes so smooth and silky that most people assume it is full of cream. It is not: just a little Parmesan and butter at the end.
Why roast the cauliflower?
Boiled cauliflower can taste watery and slightly cabbage-like. Roasting at high heat browns the edges and brings out a sweet, nutty flavor. Those caramelized bits are what make this soup taste so rich.
Garlic roasted in its skin
Roasting whole garlic cloves in their skins turns them soft, sweet and mellow. Simply squeeze them out of their papery skins into the pot. Six cloves may sound like a lot, but roasted garlic is gentle.
Creamy without cream
Cauliflower blends into a naturally velvety puree. A high-speed blender gives the silkiest texture. If you use an immersion blender, keep blending for two or three minutes until no grains remain.
Parmesan and lemon
Parmesan adds savory depth and a little body, while a spoon of lemon juice lifts the flavor and keeps the soup from tasting flat. Taste before and after the lemon to see the difference.
Low carb and keto friendly
Cauliflower is low in carbohydrates, so this soup fits a low-carb or keto diet. One serving has only about 9 grams of net carbs. Add crumbled bacon on top for extra flavor and protein.
Make it vegan
Use vegetable broth, skip the butter and replace the Parmesan with two tablespoons of nutritional yeast. A splash of coconut milk adds extra creaminess.
Flavor variations
Add a teaspoon of curry powder and cumin for a warm Indian-spiced version. Stir in white cheddar for a cheesy soup, or blend in a roasted red pepper for color.
Topping ideas
Crispy roasted florets, toasted pine nuts, crumbled bacon, a swirl of pesto, chili oil or garlic croutons all add texture and color.
Serving ideas
Serve with crusty bread or a grilled cheese sandwich. For more velvety soups, try our cream of asparagus soup or the sweet sweet potato soup.
Choosing a good cauliflower
Look for a heavy, firm head with tightly packed white florets and bright green leaves. Avoid heads with brown spots or a soft texture.
Storage
This soup keeps for 5 days in the fridge and freezes very well for up to 3 months, because it contains little dairy.
Cutting cauliflower without a mess
Remove the green leaves, turn the head upside down and cut around the core with a paring knife. The florets fall away in large pieces with far fewer crumbs. Cut them into similar sizes, about 1 1/2 inches, so they roast evenly.
Don't crowd the pan
Spread the florets in a single layer with some space between them. Crowded vegetables steam instead of browning, and you lose the toasted, nutty flavor. Use two baking sheets if needed.
A soup for meal prep
Because it holds and freezes so well, this is a great soup to make on Sunday and portion into jars for weekday lunches. Keep the crispy florets in a separate container and add them when you reheat.
Garnish
A drizzle of good olive oil, a pinch of smoked paprika and fresh chives make each bowl look and taste finished.
Frequently asked questions
Can I use frozen cauliflower?
Yes. Roast it straight from frozen at 450°F; it may need 10 extra minutes to brown.
Why does my cauliflower soup taste bitter?
The florets may have burned. Roast until golden, not dark brown, and turn them halfway.
Can I add potatoes?
Yes. One diced potato simmered with the broth makes the soup even thicker.
