Prep time 60 minutes
The key to creating a soup with a pronounced depth is using a French technique called à l’étouffée that involves simmering vegetables in a covered pot over low heat so that they steam in their own liquid.
½ cup olive oil
2 onions, thinly sliced
2 garlic, cloves thinly sliced
2 bay leaves
2 tsp fresh thyme leaves
½ cup dry white wine
1 large head of cauliflower, cut into small florets with the stem chopped
¼ tsp cayenne pepper
¾ cup cashews
6 cups vegetable stock
Ground black pepper
2 tbsp toasted cashews for garnish
1 tsp sumac for garnish.
Heat ¼ cup oil in a large heavy pot over medium. Add onion, garlic, bay leaves, and thyme; season with salt. Cook, stirring occasionally, for 6–8 minutes. Add wine, bring to a boil, and cook until reduced by half, about 4 minutes.
Set ¾ cup cauliflower aside; add the rest to pot along with cayenne and ¾ cup cashews; season with salt. Cover pot, reduce heat to low, and cook, shaking pot occasionally, until cauliflower is fork-tender and vegetables have released all their water; 20–25 minutes (check occasionally to make sure vegetables are not browning – reduce heat if they are).
Add stock and season with salt and black pepper. Bring to a boil, reduce heat, and simmer, partially covered, until cauliflower is falling apart, for about 20–25 minutes.
Discard bay leaves. Remove from heat and let cool slightly.
Meanwhile, finely chop reserved ¾ cup cauliflower and remaining 2 tbsp. cashews.
Heat the remaining ¼ cup oil in a small skillet over medium. Add cauliflower and cashews; season with salt. Cook, stirring often, until golden – for around 5–8 minutes. Remove from heat and stir in lemon juice and let cool slightly.
Working in batches if needed, purée the soup in a blender until very smooth. Return to pot and reheat over medium-low, stirring and adding more stock to thin if needed (soup should be the consistency of heavy cream). Taste and season soup again if needed. Serve soup topped with toasted cauliflower-cashew mixture and sumac.