Summer has officially arrived, and with it, the dry summer heat for which Sacramento is so well known. Chilled soups were invented for hot days like these. Vichyssoise, a chilled creamy potato and leek soup, was introduced to Americans by French chef Louis Diat at the Ritz-Carlton in New York in the summer of 1917, to help keep patrons cool.
Chilled soups used to be a lot more popular than they are these days, especially before WWII and modern air conditioning.
The original Vichyssoise is a cream bomb, calling for a quart of broth, 2 cups of milk, and 3 cups of cream, for eight servings. Yikes. That's almost a half cup of cream per serving!
Our version is decidedly lighter, though still quite creamy because we use Yukon gold potatoes, which are naturally creamy potatoes (they make great mashed potatoes too).
The soup is really easy to make, doesn't use a lot of ingredients, and lasts for days.
The trick is serving temperature. It's great hot, though it is designed to be a chilled soup. I found the best serving temperature is just below room temp. Too cold and and the flavor from the butter, potatoes, and salt just disappears.
- 4 Tbsp butter
- 4-5 cups sliced leeks, cleaned (see How to Clean Leeks), white and pale green parts only (from about 4 large leeks)
- 1 medium onion, chopped or sliced
- 2 lbs Yukon gold potatoes, peeled and chopped
- 6 cups water (vegetarian option), or chicken stock
- 2 teaspoons Kosher salt (more to taste)
- 1/2 cup sour cream
- 1/2 cup heavy whipping cream
- Chopped fresh chives for garnish
Heat butter until it begins to brown:
In a large (6-quart) pot, heat the butter on medium high heat until it melts and foams up. Continue to heat until the foam subsides a little and the butter just begins to brown.
Sauté leeks and onions:
Immediately toss in the sliced leeks and onions. Stir to coat with the butter. Cook for several minutes, reducing the heat to medium if necessary, until the leeks and onions are translucent and wilted.
Add potatoes, water or stock, salt, bring to simmer:
Add the chopped potatoes, salt, and water or stock. Bring to a boil, reduce to a simmer. Cook, partially covered for 30-40 minutes, until the potatoes are completely cooked through. Remove from heat.
Purée until smooth:
Purée using an immersion blender or working in batches, blend in a blender. (Careful! With hot liquids only fill the blender 1/3 of the way full, and hold the blender top on with your hand while blending.) Purée until completely smooth.
If you want an even smoother soup, you can take the extra step of pressing the purée through a sieve with a rubber spatula.
Cool and stir in sour cream and cream:
Allow to cool a bit before stirring in the sour cream and whipping cream. Allow to cool completely and chill in the refrigerator. The soup should be served just below room temperature (maybe 65°F or 18°C). If it is too cold, it won't taste as good.
Add more salt to taste. Serve garnished with chopped fresh chives.