Roasted Romanesco Soup

Recipe 15 minPreparation Time 45 minCooking Time
Roasted Romanesco Soup

Roasted Romanesco Soup

15 minPreparation Time 45 min Cooking Time

About this Recipe

You can make this soup with regular cauliflower, but Romanesco, with its fractal shapes and bright chartreuse color, is so entrancing. It’s a little milder, sweeter, and nuttier in flavor than cauliflower. Romanesco’s florets are also more tender; this helps make for a creamier pureed soup. Save a few pieces of roasted sliced Romanesco as garnish for the soup, so you might see a hint of its fractal forms too. The addition of buttermilk gives this soup a refreshing (and probiotic) tang.

The Benefits

Not only does Romanesco look cool, but brassicas like it (think broccoli, cabbage) are antioxidant rich. Antioxidants have potential as cancer-fighters and immunity-boosters. Romanesco also contains sulforaphane, a compound supporting the liver and detoxification.


Serves 4
  • 1 medium or 2 small head(s) of Romanesco cauliflower, about 1 lb 10 oz (760 g) total
  • 3 Tbsp (45 ml) olive or avocado oil, divided
  • 1½ tsp salt, divided
  • Freshly ground black pepper
  • 1/2 onion, diced
  • 3 garlic cloves, smashed
  • 3¼ cups (775 ml) vegetable or chicken broth
  • 1/2 cup (120 ml) buttermilk, plus more for garnish
  • Chopped chives for garnish


  1. Step 1
    Heat the oven to 425°F/220°C. Trim the base of the cauliflower. Cut the cauliflower into about 1/2-inch-thick slices and place the slices in a single layer on a baking sheet (it’s fine if they’re a bit crumbly). Drizzle and coat the slices with 2 Tbsp (30 ml) of oil and sprinkle with 1/2 tsp of the salt and a few grinds of black pepper. Roast in the oven until cooked through and the edges have browned, about 25 minutes, flipping halfway through cooking. Remove from the oven and set aside.
  2. Step 2
    Heat the remaining 1 Tbsp oil in a large pot or Dutch oven over medium-high heat. When the oil is hot and shimmering, add the diced onion and sauté until translucent, about 3 minutes. Add the garlic and cook until fragrant, 30 seconds to 1 minute. Add the roasted cauliflower, but reserve several small pieces as garnish for each bowl of soup. Add the broth, the remaining 1 tsp salt, and several grinds of pepper. Heat until warmed through.
  3. Step 3
    Remove from the heat and use an immersion blender to puree until completely smooth (or transfer the contents of the pot to a blender if you don’t have the immersion type). Put the soup back on the stove until it is just hot (do not bring to a boil). Remove it from the heat and stir in the buttermilk. Taste and adjust the seasoning. Ladle the soup into bowls and garnish with an extra drizzle of buttermilk, the reserved cauliflower pieces, and lots of chives. Serve immediately.

Try It With: Seeded whole-grain crackers 

Level Up: You can use roasted garlic in this soup: Wrap a few peeled garlic cloves, drizzled with a little olive oil, in a piece of aluminum foil and roast it along with the Romanesco