Bonny Wolf is Kitchen Window's contributing editor and a commentator on NPR's Weekend Edition Sunday. She also hosts the Kitchen Window podcast. Her book of food essays, Talking with My Mouth Full, is out in stores. You can find more information at bonnywolf.com.
One of my dinner guests insisted that the cold soup I served included lemon juice. "No," said another, "it's definitely vinegar." Both wrong. Well, the complex cream sauce on the salmon, they agreed, must have taken hours to put together. Wrong again.
The secret ingredient is sorrel, a deceptively bland-looking green that bursts with lemony tartness. Cooking with sorrel offers depth and a surprise flavor with almost no effort. It is spring's little gift to the cook.
Sorrel has a natural affinity for fish and eggs, and is the basis for many soups. When sauteed for a minute or so, it melts into a puree that, with a little butter and cream, makes a lovely, easy sauce for fish or vegetables. A sorrel cream is a perfect bed for poached eggs. It adds a fresh, tart edge to any salad.
The cold soup I served was a variation on schav, a traditional dish of Eastern European Jews who like sour tastes. It is often called white or green borscht, and is such a common part of the diet of Jews from this part of the world, it is sold bottled in supermarkets. The word "sorrel" has both German and French roots from words meaning sour.
The French have probably had the longest, most ardent love affair with sorrel. Potage creme d'oseille, also called potage Germiny for a former French finance minister, is a French classic. It is a lovely, rich cream of sorrel soup.
Another French standard is shad stuffed with sorrel. Because of its lemony accent, sorrel often is paired with fish.
The English historically have used sorrel as both a medicinal and a kitchen herb. They made a sorrel-based sweet-and-sour condiment called green sauce to eat with meats. It was so common, sorrel itself was sometimes called green sauce.
An ancient herb, sorrel was used by the Romans, Greeks and Egyptians as a digestive aid. It also was wrapped around meat to tenderize it. Sorrel's purported properties as a tenderizer and aid to digestion are related to its abundance of oxalic acid. This natural chemical gives sorrel its tart citrus flavor.
Because of its load of oxalic acid, sorrel should not be cooked in unlined aluminum or cast iron. It will turn black in color and nasty in taste. Even at their best, the bright green sorrel leaves turn a muddy green when cooked. You'll overlook the color, though, once you experience the surprising taste.
Americans, who don't generally go for the bitter, have come to sorrel late. While it has been discovered by cooks and well-traveled eaters, sorrel still is difficult to find outside farmers markets. It is, however, simple to grow from seed. Sorrel is a hardy perennial — a member of the buckwheat family — and can be sowed and reaped for many years. While there are native American wild sorrels, the varieties most often used for cooking are cultivated from European species.
Sorrel is the herb that keeps on giving. It requires almost no care aside from a little weeding, and cutting back any flower stalks that appear, sorrel will produce all summer.
When it appears in markets in mid-May, young, small-leafed sorrel is available. Like other spring greens, early sorrel is tender enough to be eaten raw. Whole small leaves can be tossed with other greens in a salad. As sorrel matures and the leaves grow larger, the acidity becomes more pronounced.
Sorrel comes in a number of varieties, most commonly with an arrowhead-shaped leaf. At farmers markets, I have found a round-leafed sorrel and one absolutely beautiful variety with deep burgundy veins. "Chefs are going to flip over this," the farmer selling it said. She labeled it "blood sorrel."
Whatever the variety, look for sorrel that is bright green with firm leaves. If leaves are limp or yellowing or the stems look woody, take a pass. Sorrel is somewhat fragile and should be refrigerated in a plastic bag for no more than three days. It can be pureed and frozen for later use.
While small, young leaves can be used whole; larger leaves will need to be stemmed and cut, or they will be tough and too strong. Fold a large leaf in half, grab the stem from the back and gently strip off any large rib or fibrous strings. Pile leaves on top of each other, roll into a cigar shape and chiffonade (cut into thin slices) with a non-aluminum knife.
That will be the hardest part. The rest is easy. Toss sorrel in a saucepan with a little water, and in a minute or two it will reduce down to almost nothing and melt into a silky puree, ready to liven up soups and sauces. It may look a little muddy, but that's to be expected from the refreshing taste of spring.
This is a variation of schav, a Jewish Eastern European cold soup. Instead of boiling the potatoes with the broth, as is common, I roast them and add them to the soup. This soup could be served as a first course for a spring dinner or as a light main course on a hot summer day. Serve with sour cream or yogurt. This recipe requires time for chilling.
Makes 6 first-course, 4 main-course servings
1 pound sorrel
1 cup water
3 tablespoons unsalted butter
1 large leek, white and light green part only, chopped
4 cups chicken stock
Salt and pepper to taste
3 medium potatoes, scrubbed and diced
1 tablespoon olive oil
1 large egg
2 large egg yolks
Yogurt or sour cream
Preheat oven to 425 degrees.
Rinse sorrel thoroughly. Remove stems and any heavy ribs from sorrel, setting them aside. Roll leaves into cigar shape and chiffonade (slice thinly). Set aside.
In a small saucepan, place stems, ribs and 1 cup water. Bring to a boil and cook for 15 minutes. Strain the liquid in a mesh strainer, rubbing the solids with a wooden spoon so all the liquid comes through. Discard the solids left in the strainer and set aside the liquid.
Melt 2 tablespoons butter in a large saucepan over medium-low heat. Sautee leeks until translucent. Add sliced sorrel. Cook briefly until sorrel shrinks and changes color to drab green. Add chicken stock, liquid from stems, salt and pepper. Simmer 15 minutes, or until sorrel has almost dissolved into the liquid.
Meanwhile, toss potatoes with olive oil, salt and pepper, place in a small roasting pan and roast, turning occasionally, for 20 minutes or until browned but not mushy.
In a small bowl, beat egg and yolks together. When broth is done cooking, pour a ladleful over eggs and whisk. Whisk egg mixture into soup.
Refrigerate both soup and potatoes overnight or for at least 4 hours.
Before serving, add potatoes. Serve with yogurt or sour cream.
Sorrel has a particular affinity for eggs and is often used in omelets, frittatas, quiches and tarts. A full-flavored cheese further enhances the combination. I use fresh goat cheese here, but you could substitute a cup of grated Gruyere. Serve warm or at room temperature.
Makes 6 servings
1/2 cup chopped shallots
2 tablespoons unsalted butter
3 cups sorrel, cleaned and thinly sliced
9-inch single pie crust
6 large eggs
Salt and pepper to taste
1/4 teaspoon nutmeg
1/4 teaspoon cayenne
1 1/2 cups milk (whole or 2 percent)
4 ounces fresh goat cheese
Parmesan cheese for sprinkling, about 1/4 cup
Preheat oven to 375 degrees.
In large saucepan, sautee shallots in butter until soft but not colored. Add sorrel and cook until wilted, a minute or two. Set aside to cool.
Meanwhile, prebake the pie crust. Line with a piece of buttered aluminum foil and fill with pie weights or dried beans. Set in oven and cook for about 10 minutes, or until rim of crust begins to brown. Remove and set aside.
Beat eggs, spices and milk together. Add sorrel and shallots. Add chunks of cheese to the mixture and stir.
Pour mixture into pie crust and sprinkle with Parmesan. Place tart in oven and bake 35 to 40 minutes, or until top is golden brown.
Let sit at least 10 minutes before slicing. Serve warm or at room temperature.
Salad Of Sorrel, Endive And Mushrooms With Walnut Dressing
This earthy salad recipe is adapted from Elizabeth Schneider's Uncommon Fruits & Vegetables (Perennial Library 1986). The sourness of the sorrel and bitterness of the endive are countered by the sweetness of balsamic vinegar and walnuts.
Makes 6 servings
1/3 cup walnuts
1 tablespoon balsamic vinegar
1 tablespoon cider vinegar
1/4 teaspoon salt
3 tablespoons walnut oil
2 tablespoons peanut oil
1/2 pound sorrel
1/2 pound Belgian endive
1/2 pound mushrooms
Pepper to taste
Preheat toaster oven to 375. Toast walnuts for 5 minutes. Cool and chop in coarse pieces. Set aside.
Combine vinegars and salt. Mix. Gradually beat in the oils. Set aside.
Strip off and discard sorrel stems and any woody ribs. Cut leaves in narrow strips. Trim bases and cores from endive, then thinly slice. Slice mushrooms thin.
Combine sorrel, endive and mushrooms in a serving bowl. Add walnuts and pepper. Pour dressing over and toss gently.
This is a standard recipe for a sorrel cream sauce to use with poached salmon or other fish. It could also be used with steamed spring vegetables such as asparagus. A pinch of cayenne and/or nutmeg is traditional.
Makes 1 cup
3 cups sorrel, cut into thin strips
3 tablespoons unsalted butter
1/2 cup heavy cream
Salt and pepper, to taste
Pinch of cayenne, nutmeg (optional)
Wash sorrel and remove stems and any woody ribs. Roll leaves into cigar shape and thinly slice.
In a large saucepan, melt butter. Add sorrel and cook, stirring, over medium heat until it melts into a puree — 2 to 3 minutes. Whisk in the cream. Simmer for another 2 to 3 minutes while adding seasonings. Sauce should thicken. The sauce can be used immediately or chilled to use with cold fish or vegetables.