Roasted Cauliflower and Garlic Soup

Name: Roasted Cauliflower and Garlic Soup
Prep time: 15 min
Cook time: 50 min
Total time: 1 h 5 min
Yield: 4 servings
Cuisine: Italian
Ingredients: 1½ lb (680 g) fresh cauliflower florets, cut into 1-inch florets; 2 bulbs (100 g) garlic bulbs, whole unpeeled, halved horizontally, top quarter removed; 5 tbsp (75 ml) extra-virgin olive oil, divided; kosher salt, to taste; freshly ground black pepper, to taste; ¾ lb (340 g) waxy potatoes (like Yukon Gold), peeled and cut into ½-inch cubes; 4 cups (960 ml) vegetable broth, warm; ¼ cup (60 ml) heavy cream, cold; 2 oz (60 g) Parmigiano-Reggiano cheese, finely grated, plus extra for garnish; 2 sprigs fresh thyme sprigs (optional); ⅛ tsp (0.6 ml) dried red pepper flakes, optional, for garnish (optional)

From the MyKitchenBank Kitchen

A silky Italian-inspired soup built on caramelized cauliflower and sweet roasted garlic, finished with a swirl of cream and shaved Parmesan. The roasting concentrates the vegetables' natural sweetness, creating depth without cream or stock as a base.

Prep: 15 min
Cook: 50 min
Total: 1 hr 5 min
Makes: 4 servings (about 5 cups / 1.2 liters)

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Ingredients

4 servings

1½ lb (680 g) fresh cauliflower florets, cut into 1-inch florets
2 bulbs (100 g) garlic bulbs, whole unpeeled, halved horizontally, top quarter removed
5 tbsp (75 ml) extra-virgin olive oil, divided
kosher salt, to taste
freshly ground black pepper, to taste
¾ lb (340 g) waxy potatoes (like Yukon Gold), peeled and cut into ½-inch cubes
4 cups (960 ml) vegetable broth, warm
¼ cup (60 ml) heavy cream, cold
2 oz (60 g) Parmigiano-Reggiano cheese, finely grated, plus extra for garnish
2 sprigs fresh thyme sprigs (optional)
⅛ tsp (0.6 ml) dried red pepper flakes, optional, for garnish (optional)

Equipment (6)

Two large rimmed baking sheets
Large heavy-bottomed pot or Dutch oven (5-quart / 4.7-liter)
Immersion blender or standard blender
Chef's knife and cutting board
Wooden spoon
Measuring cups and spoons

Steps

Before you start

Preheat oven to 425°F (220°C) at least 15 minutes before roasting
Have vegetable broth measured and ready to add
Gather all ingredients and prep vegetables

1
Roast the vegetablesOven 425°F / 220°C
- Divide the cauliflower florets and halved garlic bulbs between two large rimmed baking sheets.
- Drizzle with 4 tablespoons (60 ml) of the olive oil, season generously with salt and black pepper, and toss well to coat.
- Spread in a single layer with the garlic halves cut-side down.
- Roast at 425°F (220°C) for 35–40 minutes, stirring the cauliflower halfway through, until the florets are deeply browned and caramelized at the edges and the garlic is completely soft and golden.
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Ready when: Cauliflower is deeply browned and caramelized; garlic is soft and golden
Tip: Arrange cauliflower in a single layer without crowding—overlapping will steam rather than roast.
2
Cook the potatoes
- While the vegetables roast, heat the remaining 1 tablespoon (15 ml) of olive oil in a large heavy-bottomed pot over medium heat.
- Add the cubed potatoes and cook for 3–4 minutes, stirring occasionally, until they begin to soften slightly and turn translucent at the edges.
- Add the warm vegetable broth and bring to a gentle simmer.
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Ready when: Potatoes soften slightly and broth simmers gently
3
Add roasted vegetables to broth
- Once the roasted vegetables are done, transfer them to the pot with the simmering broth.
- Using a spoon, squeeze the soft roasted garlic cloves out of their skins into the pot, discarding the papery husks.
- Bring the soup back to a gentle simmer and cook uncovered for 8–10 minutes to allow the flavors to meld.
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Ready when: Soup simmers gently and potatoes are completely tender when pierced with a fork
Tip: If your garlic halves cool quickly, return them to the oven for 2 minutes before squeezing out the cloves.
4
Blend the soup
- Turn off the heat and let the soup cool for 2–3 minutes.
- Using an immersion blender, blend the soup until completely smooth, working in batches if needed and being careful not to splatter.
- If using a standard blender, let the soup cool slightly, then carefully transfer in batches, covering the lid loosely with a kitchen towel when blending hot soup, and return each batch to the pot.
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Ready when: Soup is completely smooth with no visible chunks
Tip: An immersion blender is fastest here; if using a standard blender, cover the lid loosely to allow steam to escape.
5
Finish with cream and cheese
- Return the pot to medium-low heat if needed.
- Stir in the grated Parmesan cheese and cold heavy cream, stirring gently until the cheese melts and the cream incorporates, about 1–2 minutes.
- Do not allow the soup to boil, as the cream may curdle.
- Taste and adjust seasoning with salt and black pepper as needed.
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Ready when: Cheese dissolves completely and soup is creamy and smooth
Tip: Keep the heat low to prevent the cream from curdling; stir constantly.
6
Serve
- Ladle the soup into four warmed bowls.
- Garnish each bowl with a light drizzle of extra-virgin olive oil, a few fresh thyme leaves if using, a pinch of red pepper flakes for heat, and a light shower of grated Parmesan.
- Serve immediately while hot.
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Tip: Warm the bowls by filling them with hot water and pouring out just before serving for a better presentation.

Good to know

Tips

Roasting is key to this soup's depth—don't skip it or rush it. Deep caramelization of the cauliflower takes time and creates a rich, almost nutty base.
Squeeze the garlic cloves out of their papery skins with a spoon—they'll be buttery soft and naturally sweet after roasting.
If the soup is too thick after blending, thin it with a little warm broth or milk stirred in a splash at a time until you reach your desired consistency.
Serve with crusty bread or pair with a simple salad for a light vegetarian lunch or dinner.

Make ahead

The soup can be made up to 2 days ahead through the blending step. Cool completely and refrigerate in an airtight container. Reheat gently over medium-low heat, stirring occasionally, then stir in the cream and Parmesan just before serving.

Storage & reheating

Room temperature: up to 2 hours (allow to cool, then refrigerate). Refrigerator: up to 3 days in an airtight container. Freezer: up to 1 month in a freezer-safe container (freeze before adding cream; thaw overnight in the fridge, then reheat gently and add cream and Parmesan). To reheat: Warm over medium-low heat, stirring often, until steaming. If reheating from frozen, allow extra time and stir occasionally.

Substitutions

waxy potatoes (like Yukon Gold) → Celery root or white beans. Either creates a silky body without potatoes. Celery root adds a subtle earthiness; white beans (canned and drained) add protein.
heavy cream → Whole milk or Greek yogurt. Use 1/3 cup (80 ml) whole milk for a lighter soup, or stir in 2–3 tablespoons (30–45 ml) Greek yogurt off the heat for tang.
vegetable broth → Water with 1/2 teaspoon (2.5 ml) salt per cup. A neutral broth; the roasted vegetables provide most of the flavor.
Parmigiano-Reggiano cheese → Pecorino Romano or Grana Padano. Use the same amount; Pecorino is sharper, Grana Padano milder.