There are few French soups as classic and simple as the wintry combination of leeks and potatoes, a dish known as potage Parmentier, named after Antoine-Augustin Parmentier, the Frenchman who popularized the potato in France.

The ubiquity of potato-based dishes might have you believe that it has always been a staple of French cuisine, yet before this 18th-century pharmacist/agronomist began promoting its nutritional and culinary benefits, it was used only as animal feed and was believed to cause leprosy. It was only through years of research and potato campaigning (that even included potato-themed supper clubs for celebrity guests) that the French finally began to accept the humble potato as a safe and delicious ingredient.

Why tell this story? In our hectic lives, grabbing familiar ingredients from supermarket shelves without a second thought, we can easily forget the value of our food – how it was produced or the culinary history of how it arrived at our table to nourish us. Knowing the history of food, how it has traveled to us through time as well as space, brings a dish alive and helps us to connect to it on a deeper level. So perhaps as you prepare this inexpensive and healthy soup you can imagine the revolutionary Parmentier gifting bouquets of potato blossoms to Queen Marie-Antoinette and King Louis XVI and paving the way for the invention of the French fry.

While most classic versions embellish the preparation with cream and milk, we find that if you choose top-quality vegetables and a sturdy, rich vegetable or chicken stock, you can easily forego the dairy.

Here we use only the white part of the leeks, saving the green tops to create a crunchy zero-waste garnish. Of course it’s more of an inspired-by version than a true tempura, tossing blanched leek tops in arrowroot or cornstarch and frying in olive oil to give a light crispy exterior to the soft vegetable interior.

If you don’t have time to make the topping, save the green tops in freezer to add to a flavorful stock.

Potage Parmentier: Leek and Potato Soup

4 servings as a main, 8 as a starter   |   Equipment: A large, heavy stockpot; a small saucepan; a clean kitchen towel; a small sieve; a small nonstick skillet; a blender; 8 warmed, shallow soup bowls

Ingredients

1 onion, peeled and cut into thin half moons
5 tablespoons extra-virgin olive oil
1/2 teaspoon fine sea salt and more to taste
1 pound (500 g) waxy potatoes, such as Yukon gold, cubed (do not peel)  
1 pound (500 g) white part of leeks, halved lengthwise, cut into thin half moons
1 1/2 quarts (1.5 l) rich chicken or vegetable stock
4 fresh bay leaves

Garnish

1/2 teaspoon sea salt
Green leek tops, rinsed and cut into thin 1 inch (2-3cm) strips
2-3 tablespoons arrowroot or cornstarch,
3 tablespoons extra virgin olive oil, plus extra if needed

Method

1.     In the stockpot, combine the onions, oil, and salt and stir to coat the onions with the oil. Sweat – cook, covered, over low heat until soft – about 5 minutes. Add the potatoes and leeks and and cook until they begin to soften, stirring regularly, about 5 minutes. Add the stock and bay leaves and cook until the vegetables are soft, about 25 minutes. 

2.     To make the garnish: While the vegetables are cooking, bring 1/2 cup (125 ml) water to a boil in the small saucepan and add the sea salt. Quickly blanch the leek strips in the water until soft, about 1 minute. Strain and pat the leeks dry with a clean kitchen towel.

3.     Place the arrowroot in a small bowl and add the blanched leek strips, tossing to coat completely. Spoon the strips into the sieve and lightly shake to remove the excess arrowroot. Heat the olive oil in the small skillet over medium-to-high heat. Add the leeks strip-by-strip, so they don’t bunch together and toss in the olive oil. Fry until crispy, about 30 seconds to a minute. Be careful as they can burn quickly. Remove from the pan and set aside. Lightly season with sea salt. Note, you may need to fry in batches, adding extra olive oil as needed.

4.     Once the potatoes and leeks are cooked through, take off the heat and remove and discard the bay leaves. Transfer the mixture to the blender and blend until smooth. Taste for seasoning. To serve, pour into the warmed soup bowls and garnish with the leek tempura.

This is a Nourish the Planet recipe, part of a collaborative series by Patricia Wells and Emily Buchanan.
© 2021 – All rights reserved. Please do not reproduce without permission.

Find our more here about why we created this series.