Creamy Roasted Cauliflower Soup

Bahan-bahan (4 porsi)

• 1 large head cauliflower (about 2 pounds), cut into bite-size florets
• 3 tablespoons extra-virgin olive oil, divided
• Fine sea salt
• 1 medium red onion, chopped
• 2 cloves garlic, pressed or minced
• 4 cups (32 ounces) vegetable broth
• 2 tablespoons unsalted butter
• 1 tablespoon fresh lemon juice, or more if needed
• Scant ¼ teaspoon ground nutmeg
• For garnish: 2 tablespoons finely chopped fresh flat-leaf parsley, chives and/or green onions