Zucchini Basil Soup with Crème Fraîche and Pickled Corn
Gussy up your garden-variety zucchini soup with loads of leeks and basil, piquant pickled sweet corn, and a swirl of tangy crème fraîche; it's equally good hot or cold.
Prep: 1 hour
Total: 1 hour
Servings: 4 large or 6 small servings
- 2 medium corn cobs
- ½ small shallot, peeled and finely diced
- ½ teaspoon fine sea salt
- 2 tablespoons champagne vinegar, (30 ml)
- 3 medium leeks , (500 g)
- 2 tablespoons butter, (30 g)
- 1 ¼ pounds zucchini, trimmed and chopped into roughly 1/2″ pieces, (about 6 small / 570 g)
- 1 medium yukon gold potato, peeled and chopped, (200 g)
- ½ teaspoon salt, more as needed
- Freshly ground black pepper
- 4 cups water, (950 ml)
- juice of ½ a lemon
- leaves from 1 large or 2 small bunches basil, plus a few pretty sprigs for garnish, (2-3 cups lightly packed)
- crème fraiche, for serving
Make the corn:
Shuck the corn cobs and remove the silk. Hold a cob upright in a shallow bowl and use a small, serrated knife to slice off the top 2/3 of the corn kernels, sawing with a downward motion. Repeat with the second corn cob. Add the shallot to the corn, then toss with the vinegar and salt. Cover and chill until needed, at least 1 hour and up to 1 week, stirring a few times.
Make the soup:
Slice the leeks in half lengthwise, then cut the white and light green parts crosswise into ½” thick pieces. Place the leeks in a large bowl, cover with cool water, and let stand 5 minutes and swishing occasionally; any sandy dirt stuck in the leek’s layers will sink to the bottom.
In a large saucepan or soup pot, melt the butter over medium heat. Scoop the leeks from their water and add to the pot along with the potato, stirring until softened, 5 minutes. Add the zucchini and cook, stirring occasionally, until the zucchini is fairly soft, 5 minutes. Add the salt, a few turns of pepper, and enough water to just cover the vegetables. Increase the heat and bring the soup to a boil, then reduce the heat to medium-low and simmer, partially covered, until the zucchini and potato are very soft, about 15 minutes. Remove from the heat and let cool to room temperature, about 1 hour.
Meanwhile, bring a medium saucepan of water to a boil, and prepare an ice water bath. Reserve a few pretty sprigs of basil for garnish, and add the rest to the pot of boiling water. Cook until bright green, 20 seconds or so, then scoop out with a slotted spoon and plunge into the ice water bath, swishing until cold. Remove the basil from the ice bath and squeeze dry.
Scoop the solids out of the soup pot with a slotted spoon and place in the bowl of a blender or food processor (you may have to do this in batches). Add the blanched basil and a bit of the cooled soup liquid. Puree smooth, adding as much broth as you need to make a creamy soup. Blend in 2 tablespoons of the lemon juice and taste, adding more lemon, salt, or pepper if you feel the soup needs it. Blend in a few tablespoons of crème fraîche if you want a creamier soup.
To serve, return the soup to the pot over medium heat to warm, stirring occasionally. Ladle into bowls and serve with a swirl of crème fraiche, a scoop of pickled corn, and a few basil leaves.
Cooling the soup and blanching the basil before blending help preserve the soup's bright green hue.
Small zucchini tend to have the best flavor; if your zucchini are large, you may need to punch up the flavor with a cube of bouillon or some vegetable stock in place of the water.
Serve this soup warm on cool summer evenings, or serve chilled thinned with extra broth and enough lemon juice to brighten the flavors.
Trade the butter for light olive oil and leave off the crème fraîche for a vegan variation.
Nutritional values are based on one of four servings.
Calories: 209kcal | Carbohydrates: 29g | Protein: 6g | Fat: 9g | Saturated Fat: 5g | Cholesterol: 21mg | Sodium: 691mg | Potassium: 850mg | Fiber: 5g | Sugar: 10g | Vitamin A: 2365IU | Vitamin C: 45.1mg | Calcium: 117mg | Iron: 3.9mg