This soup is silk-smooth with a bright, slightly tart apple lift and an earthy celery-root backbone. Roasted celery root adds caramelized depth while a touch of cream rounds the edges without cloying. Fresh tarragon and a squeeze of lemon lift the finish, keeping the bowl lively rather than heavy. Serve warm as a starter for a cozy fall dinner or with crusty bread for an easy weeknight supper.
Ingredients
- Celery root (celeriac), peeled and diced (1 lb / 450 g)
- Granny Smith apple, peeled, cored, and diced (1 large)
- Leek, white and pale green parts only, thinly sliced (1 medium)
- Garlic cloves, minced (2 cloves)
- Extra-virgin olive oil (2 tbsp)
- Unsalted butter (1 tbsp)
- Low-sodium vegetable or chicken stock (4 cups / 950 ml)
- Heavy cream or crème fraîche (1/3 cup / 80 ml)
- Fresh tarragon leaves, chopped (2 tbsp)
- Lemon juice (1 tbsp)
- Salt (1 tsp, plus more to taste)
- Freshly ground black pepper (to taste)
- Fresh sage leaves for frying (8–10, optional) or toasted pepitas for garnish
Instructions
- Preheat the oven to 425°F (220°C). Toss the diced celery root and apple with 1 tbsp olive oil and a pinch of salt on a rimmed baking sheet. Roast until golden and tender, 25–30 minutes, turning halfway.
- Meanwhile, heat the remaining 1 tbsp olive oil and the butter in a heavy pot over medium heat. Add the sliced leek and a pinch of salt and cook, stirring, until soft and slightly caramelized, about 6–8 minutes. Add the garlic and cook 30 seconds more.
- Transfer the roasted celery root and apple to the pot. Pour in the stock, bring to a simmer, then reduce heat and simmer gently for 10–12 minutes to meld flavors.
- Use an immersion blender to puree the soup until completely smooth, or carefully transfer batches to a blender and puree. Return to the pot and reheat gently—do not boil.
- Stir in the cream, chopped tarragon, and lemon juice. Taste and adjust salt and pepper. If you prefer a thinner soup, add up to 1/2 cup extra stock.
- If using sage, heat 2 tbsp oil in a small skillet over medium-high heat and fry the leaves 10–15 seconds until crisp; drain on paper towels. Ladle soup into bowls and garnish with fried sage or toasted pepitas and a few extra tarragon leaves.
Tips or Variations
- For a dairy-free version, substitute full-fat coconut milk for the cream and omit the butter.
- Add a small potato (about 6 oz) with the celery root for an even silkier texture and a milder flavor.