3.16.2014

Soup Sundays: Potato-Leek Soup

Potato-leek soup

Tomorrow is St. Patrick's Day! How are you celebrating? When I was younger, there was never any doubt that I was heading out after work with friends for a few pints of Guinness and some corned beef sandwiches at a local pub. These days I'm happy to just head home after work and avoid the crowds. I sound so old. It's probably going to sound even worse when I say I just want to curl up with a bowl of this potato-leek soup and hang out on the couch. Yup, that would be my ideal St. Patrick's Day this year.

Potato-leek soup

Let's talk about this soup, and why I'd rather have a bowl of it than hang out in long lines waiting to get into a packed bar where I know I'd have to throw elbows just to eke out a little spot to stand in. This potato-leek soup is loaded with leeks and balanced with just a little bit of potato, but it still has intense mashed-potato-like flavor and consistency. It's super-thick and creamy, without having any cream in it. Really -- butter's the only dairy to be found. The secret? A slice of sourdough bread.

Potato-leek soup

It starts with some chicken broth (vegetarians -- feel free to swap in vegetable broth) that gets flavored with the dark green parts of the leeks. The dark green parts simmer in the broth until they're softened and then they get discarded.

Next, the white and light green leek parts and some onion get softened in butter. The leek-enhanced broth gets poured over and potato slices go in. Once the potatoes are tender, the bread cubes go in. And once the bread is softened, the whole thing gets buzzed with an immersion blender.

Potato-leek soup

But I skipped the best part: the fried leeks. While you prepare the soup and it simmers away, you can make some fried leeks to garnish the soup. They're a little crunchy and a little salty, a sort of sophisticated onion ring. They add texture and interest to an otherwise one-textured soup.

Fried leeks

I'm leaving it up to you… spend tomorrow evening fighting the bar crowds or spend a little time in the kitchen and dip into this bowl of comfort.

Potato-Leek Soup
(adapted from Cook's Illustrated)

Potato-leek soup

This potato-leek soup is thick and creamy with lots of flavor from both of its namesake ingredients.

Prep Time: 15 minutes
Cook Time: 1 hour
Yield: about 4 servings

Ingredients

3 leeks, halved lengthwise and washed thoroughly, trim off dark green parts but reserve 2 to 3 inches from each leek
2 
cups chicken broth
2 
tablespoons Kerrygold unsalted butter
½ cup chopped
 onion
Kosher salt and pepper
½ 
small russet potato (3 ounces) peeled and cut into ¼-inch-thick slices
1 sprig fresh thyme
1 small
 slice sourdough bread, toasted and cut into ½-inch pieces
1 tablespoon flour
¼ cup olive oil

Preparation

Combine the dark green leek parts and the broth in a Dutch oven or heavy pot and bring to a boil over high heat. Reduce the heat to low, cover, and simmer for about 15 minutes, or until the leeks are softened. Strain the broth through a colander set over a medium bowl. Press on the leeks to extract as much liquid as possible; set aside. Discard the dark green leek parts and rinse out the pot.

Simmering dark green leek partsDraining dark green leek parts

Thinly slice 2½ leeks. Melt the butter in the pot over medium-low heat. When the butter foams, stir in the sliced leeks, onion, and ½ teaspoon salt. Reduce the heat to low and cook the vegetables, stirring frequently, until they are softened, about 10 minutes.

Sautéing sliced leeksSautéed sliced leeks

Increase the heat to high, stir in the reserved broth, the potato slices, and the thyme sprig and bring the mixture to a boil. Reduce the heat to low and simmer until the potato slices are tender, about 10 minutes. Add the toasted bread and simmer until the bread is completely saturated and starts to break down, about 5 minutes. Turn off the heat.

Making potato-leek soupMaking potato-leek soup

Meanwhile, cut the remaining ½ leek into thin 2-inch strips. Toss the leek strips with the flour, a pinch of salt, and a pinch of pepper. Line a large plate with paper towels. Heat the oil in a 10-inch skillet over medium-high heat until shimmering. Add the leek strips and fry them, stirring often, until they’re golden brown, about 6 minutes. Using a slotted spoon or tongs, transfer the fried leeks to the paper-towel-lined plate. Season with salt and pepper to taste.

Tossing sliced leeks with flourFrying leeks

Fried leeks

Discard the thyme sprig from the soup. Using an immersion blender, process the soup until smooth and creamy. (If the soup is too thick, add water to thin it to your desired consistency.) Season the soup with salt and pepper to taste. Ladle the soup into bowls, garnish it with fried leeks, and serve.

Pureed potato-leek soupPotato-leek soup

Potato-leek soup

How are you celebrating St. Patrick's Day this year?