An added bonus to making soup: it's the perfect medium for throwing in any random items which you haven't gotten around to using but are taking up valuable refrigerator space. Case in point - I used up these three items in my soup:
Asparagus: One pound still sitting in my fridge from last weekend's farmer's market.
Buttermilk: 1 cup left over from last week's soft shell crabs - but I'm actually glad I had it on hand, as it adds a tangy creaminess that complements the asparagus nicely.
Lemon juice - I have a ton left from the lemons I peeled to make limoncello (I juiced all 10 lemons and saved the juice in a squeeze bottle). Of course, it does give the soup necessary acidity and brightens all the flavors!
I wanted to buy as few ingredients for this soup as possible - all I picked up were leeks for flavor and texture, and potatoes to thicken the soup. You really don't even need chicken stock because you can make your own asparagus stock with the woody ends which would normally be discarded. With some fresh herbs to complete the dish (I used a little tarragon from our "garden") you'll have a lovely chilled soup that is perfect for summer and won't cost more than a few dollars.
By the way, if you're making a puree like this one, get your hands on an immersion blender. Especially if you hate washing appliances like I do, the whole pureeing process is infinitely less daunting when you don't have to worry about pouring soup from the pot into the blender and back again.
Chilled Asparagus and Leek Soup
2-3 large leeks (white and tender green parts only), washed and chopped
1 large bunch asparagus, sliced into 2-inch segments (don't discard woody ends)
2 medium potatoes, peeled and cut into one-inch cubes
1 cup buttermilk
1/4 tsp paprika
1/4 tsp fresh grated nutmeg
1/8 cup lemon juice
1/8 cup fresh tarragon
Bring 2 quarts of salted water to a boil, then add asparagus segments (including woody ends) and cook until just barely tender, 3-4 minutes. Immediately transfer asparagus into an ice bath, but reserve cooking liquid and continue to boil over medium-high heat. Swirl ice bath to allow asparagus to cool, then separate out asparagus tips and reserve in a second bowl. Return woody ends to the asparagus cooking liquid and continue to boil in order to create asparagus stock.
Heat 3 tbsp butter in a large, heavy pot over medium heat. Saute leeks until soft, about 10 minutes. Add asparagus and potatoes and stir until well combined.
Using an immersion blender, puree the asparagus soup mixture.
Taste and correct seasoning if necessary. Allow soup to cool for 20-30 minutes off heat, then whisk in buttermilk. Add lemon juice, salt, and pepper to taste, then chill in the refrigerator for at least 2 hours.
Top with reserved asparagus tips and a little fresh parsley before serving. Makes 4 servings as a main dish, though this soup would also make a wonderful appetizer course.
In case you're wondering what else is on the plate, I served my soup alongside toasted bread and a simple salad (arugula, French breakfast radishes, lemon juice, olive oil, salt, and pepper).
Very refreshing on this hot summer night!