Revenge, patient people tell us, is a dish best served cold. I feel the same way about soup, at least at this time of year. When it gets hot, there are few things that will whet a flagging appetite like a sip of cold soup.
What's even better, they're so easy to make. Puree tomatoes, soaked bread, garlic, assorted vegetables and good Spanish olive oil and you've got gazpacho. Blend avocado with cold chicken stock and you've got the base for something equally grand.
Just as easy, but seen a lot less often, are cold dairy soups — based on tart buttermilk or yogurt. You can make them as simple as grated cucumbers stirred into yogurt or something much more elaborate. And there are few dishes more refreshing.
For the most part, these soups work best as appetizers. I remember one of the first fancy dinners I ever made was for my parents. I labored for a couple hours on a lovely Hungarian cherry soup that Richard Olney had collected in one volume of his "The Good Cook" series. It really was something — you pitted sour cherries, then made a quick stock with the cracked pits (I used a hammer), a cinnamon stick and Riesling, then brought everything together with sour cream and chilled it. Everyone seemed to enjoy it, and I basked in much praise.
But when we were finished, everyone sat looking around at each other, wondering who was going to be the first to ask where the main course was. We went out for burgers, if I recall correctly.
But just because they won't stand in for a full meal doesn't mean these soups are in any way slight. Easy to make? Sure. But you still need to pay attention to the details. And they take a certain amount of patience.
Maybe the most important thing to remember: The freshly made soup is little more than a rough draft. Unlike a hot soup, which is usually ready to eat as soon as you're done cooking, you really need to give cold soups a couple hours to chill before serving them. And you'll definitely need to go back after the soup's been thoroughly chilled and fine-tune the seasoning and the texture.
Cold dulls flavor; you'll almost certainly want to add more salt and pepper and maybe more acidity. Season generously to start and don't be afraid to add more just before serving.
At the same time, vegetables sometimes give up liquid, which will thin the soup. On the other hand, starches can absorb some of that liquid, which will make the soup thick and muddy. That's easy to fix, with the addition of a little milk. But it's better to start with a soup that's a little thick, because it's a lot easier to thin a soup than to thicken it.
A dairy background makes an ideal blank canvas for experimentation. For example, blend radishes and their blanched tops with buttermilk, green onions and a little garlic and you've got a soup that's pretty nice— tart and spicy with bits of crunch. Float thinly sliced radishes on top and drizzle with a little green oil made from those peppery tops and you've got something elegant enough to start a nice dinner party.
And every once in a while, these cold soups actually can make a whole meal. Grate cucumbers into yogurt with some chopped jalapeno and minced red onion and you've got an appetizer. Add cooked barley and it makes a satisfying light dinner. Top it with a Mitteleuropa mixture of dill and mint, chopped walnuts and a dash of paprika, and you've got a feast.
No after-dinner burger runs necessary.
Buttermilk Soup With Radishes and Peppery Green Oil
Serves 6; 25 minutes, plus chilling time
2 bunches radishes, with their tops
1 clove garlic, chopped
1 bunch green onions, chopped green and white parts
3 cups buttermilk
1 cup sour cream
1 1/2 teaspoons salt
1/2 teaspoon white pepper
1/2 cup olive oil
Trim the green tops from the radishes and rinse them well, discarding any that are discolored or wilted. Blanch in a 1-quart saucepan full of rapidly boiling salted water just until they are tender, about 30 seconds. Drain and transfer to a bowl full of ice water to stop the cooking. Squeeze dry and chop coarsely. Reserve 2 tablespoons to make the oil.
Quarter all but 4 of the radishes. In a food processor, coarsely grind the quartered radishes, most of the blanched tops, garlic and green onions.
Transfer the mixture to a large bowl or pitcher, add the buttermilk and sour cream and stir well to combine. Season aggressively with salt and white pepper. Chill for a couple hours.
While the soup is chilling, blend the reserved 2 tablespoons blanched radish tops with the olive oil until smooth and strain it through cheesecloth into a bowl. Do not press or squeeze the solids or the results will be cloudy.
To serve, taste and adjust seasoning for salt and pepper. Thinly slice the remaining radishes. Divide the soup among 6 chilled bowls. Float the sliced radishes on top and drizzle with a little of the green oil.
Cucumber and Yogurt Soup With Barley
Serves 6; 45 minutes, plus cooling and chilling times
1 cup pearl barley
3 cups water
1 pound small cucumbers
4 cups yogurt
2 cloves garlic, minced
2 to 3 tablespoons finely diced, seeded jalapeno pepper
1/3 cup finely diced red onion
1 tablespoon chopped mint, divided
3 tablespoons chopped dill, divided
1 to 1 1/2 cups milk
1/2 cup walnuts, chopped
Cook the barley: Toast it in a dry 1-quart saucepan over medium heat until it smells browned. Remove the pan from the heat to avoid spattering and add the water and 1/2 teaspoon salt. Simmer until tender, about 35 minutes. Drain and cool to room temperature.
If the cucumbers have been waxed, peel them. Cut the cucumbers in half lengthwise and scrape the center with a spoon to remove the seeds. Grate the cucumber into a large bowl and add the garlic, jalapeno, red onion, 2 teaspoons mint and 2 tablespoons dill. Add the yogurt and cooked barley, season aggressively with salt, and chill for a couple of hours.
To serve, add just enough milk to thin to the consistency of heavy cream (the cucumber will release some liquid, and the barley will absorb some, so the amount might vary). Add more salt to taste. Divide the soup among 6 chilled soup bowls. Top with the remaining 1 teaspoon mint, 2 teaspoons dill, a sprinkling of chopped walnuts and a dash of paprika.