Chilled potato and leek soup
The weather is getting warmer than most are used to this time of year, particularly here in the Flathead, so the last thing many of us are craving is hot potato soup. A chilled soup sounds more inviting, and one that comes to mind is gazpacho, although we are still a little too early in the tomato growing season (for those of us with gardens). This sets the stage for what I believe is the next best cold soup, especially to enjoy on a hot summer's day, the classic Vichyssoise (French for chilled potato-leek soup). A simple yet decadent concoction, it's a luxuriously creamy soup that is remarkably refreshing and satisfying, one that is sure to delight even the stingiest of palates.
The trick to this classic dish is to evenly dice and then sweat the mirepoix (also a French term for chopped aromatic vegetables, in this case, it's onion, celery and leek) in butter over medium-low heat until translucent, or just before the mirepoix begins to turn color. The longer the sweat the better, just don't allow the vegetables to brown (reduce heat to low if necessary to continue sweating). Another secret is to rinse the diced potatoes in cold water to remove some of the potato starch. Also, make sure the stock is plenty cold prior to adding to the pot.
White pepper and cayenne pepper are extremely strong spices that can quickly take a dish out of balance. The first time you make this soup, start with the tiniest amount (even a few specs can make a significant difference). Spices are meant to enhance foods and not dominate, especially when it comes to French cooking, so if you can taste the spice that's usually an indication that you've used a little too much. Lastly, feel free to substitute broth in place of stock- just be sure to account for the salt that usually accompanies broths (i.e. use less salt if using broth).
I hope you have fun and enjoy making this relatively simple soup, especially while serving it to those picky eaters, as it's always pleasurable to cook something that appeals to virtually everyone.
YIELD: 8 servings
INGREDIENTS
2 oz unsalted butter (½ stick)
1 c sweet onion, small dice (Maui, Walla Walla or Vidalia)
1 c celery, small dice
6 c leeks, sliced (white and very pale green parts only, rinse well to remove dirt) 4 garlic cloves, minced
1 bunch of green onions, sliced (green parts only)
2 lbs russet potatoes, peeled, medium dice, rinsed in cold water
1 oz fresh thyme sprigs (tied together with butcher twine)
½ gal chicken stock (or vegetable stock for vegetarian/vegan)
2 t Fleur De Sel (or kosher salt)
smidgeon of ground white pepper
smidgeon of ground cayenne pepper
⅛ t nutmeg
1 small bay leaf
1 c whole milk (or oat milk to vegan)
1 c heavy whipping cream (or coconut milk for vegan)
Garnish: minced chives, picked chive flower (optional), truffle oil (optional), dollop of creme fraiche or sour cream (optional)
INSTRUCTIONS
1 Once all ingredients are prepped, place a large saucepan or soup pot over medium heat. When the pan is hot, add the unsalted butter, as well as the onions, celery and leek, stirring to combine. Reduce heat to medium low and continue to sweat, stirring often, until vegetables (mirepoix) are fully sweated, and onions are translucent.
2 Add garlic, green onions, bay leaf, nutmeg, white and cayenne pepper, thyme sprigs and salt, stirring constantly, for about 1-2 minutes. Add rinsed potatoes, stir to combine, then add the cold chicken stock to the pot, increase heat to medium, allow the mixture to come to a consistent simmer.
3 Reduce heat to a gentle simmer, continue cooking until potatoes are fully cooked (you can use a small knife to test potatoes for doneness), about 35-50 minutes (depending on size of potatoes and thickness of the pot used).
4 Remove thyme sprigs and bay leaf, then prepare to blend/puree the soup. A Vitamix or Blendtech is ideal, while an immersion blender or food processor will also do the trick. Blend hot soup until it is fully pureed and smooth. Next, return the puree to the pan, heat over medium heat, and whisk in the milk and cream until blended and gently simmering. Adjust seasoning, if necessary.
5 Chill soup overnight or at least 6 hours before serving. The soup improves over time, as the flavors begin to meld together. Serve chilled soup with minced chives, and the other garnishes (optional), enjoy!
Notes: For a vegan-friendly recipe, use olive oil or plant-based butter in place of unsalted butter; as well as oat milk in place of regular milk and coconut milk in place of cream, following the same formula as above.
Andy Blanton is the executive chef at Flathead Valley Community College’s Culinary Institute of Montana. For more information visit fvcc.edu/culinary.