To most americans, the tomatillo is a mysterious ingredient. And it’s no wonder. Resembling a small green tomato encased in a drab papery husk, the plum-sized fruit is an unusual package. In fact, some say tomatillos resemble Chinese lanterns, because they’re cloaked in papery calyxes that surround them like Oriental lampshades. However, the fruit (also called the Mexican Green Tomato, Jamberry, and Husk Tomato) is the puckery base of the most popular Mexican green sauces. Cultivated since Aztec times, the fruit has stayed close to home; it’s rarely found outside the U.S. and Mexico. Like tomatoes, tomatillos are members of the nightshade family. Their husk is a hint that the tomatillo is related to two fruits with similar wrappings, the ground cherry, and the Cape gooseberry, all members of the Physalis species.

On the average, tomatillos weigh 11⁄2 oz. Although the fruit can ripen to yellow and then purple, they’re typically used while still green and firm. Tomatillos have an appealing tartness that enhances the flavor of virtually any ingredients they’re paired with. The distinctive taste has hints of lemon, lime, green apple, and herbs. Tomatillos are grown in Mexico and Central California, and are available year-round.

When purchasing, always choose fruits that are firm, dry, and unblemished with tight-fitting husks. Stored in an open bag in the refrigerator, tomatillos will last several weeks. Before using, peel off the crackly husk, then gently rinse the fruits to remove the sticky, resinous material near the stems. Tomatillos are essential in Mexican and Southwestern cooking, and are used raw and cooked in a variety of dishes. Their unique, slightly gelatinous texture and citric taste lend body and a bright flavor to sauces. In most recipes, tomatillos are cooked, but they can also be used raw for a more sharply acidic flavor. Uncooked tomatillos can be chopped and used in salads, gazpacho, or guacamole. They can also be sliced and used in sandwiches, or as a garnish for cold soups. Chopped and pureed with other vinaigrette ingredients, tomatillos make a distinctive dressing for green, grain, or bean salads.

Blanching or steaming tomatillos softens the their tough skin and yields a milder, smoother flavor. Because the fruit contains pectin, a sauce made with cooked tomatillos will thicken upon standing. It can be thinned with water or broth, or simply re-blended. Canned tomatillos are also available; they offer a less vibrant flavor and color, and a slightly mushier texture than fresh. To use them, simply drain and rinse.

When it comes to applications, the most time-honored uses for the tomatillo, such as salsa cruda or salsa verde, are hard to beat. The cooked sauce enhances tacos, cheese, potatoes, eggs, or enchiladas. Blended with herbs, seeds, nuts, stock, or other vegetables, tomatillos are the foundation for an array of green sauces in which chicken, turkey, fish, or vegetables and beans are simmered. 

If a tomatillo dish is going to be eaten right away, there is no need to cook the fruit. However, if you are making a sauce that will be used the next day, the tomatillos should be cooked until just tender. The reason? An uncooked tomatillo will discolor after 8-10 min. When it comes to preparing fresh tomatillos, two methods seem to offer the best results:

1. Barely cover the husked, rinsed tomatillos with cold water; poach gently, without simmering, until tender, 2-15 min., depending on the firmness of the fruit.

2. Roast unhusked, rinsed tomatillos in a dish in a preheated 450-500° F. oven until tender, 10-15 min. Watch closely so that they do not burst. Remove and let cool until you can handle easily. Pull back and twist off husks. Rinse the tomatillos gently.