Though it is treated like a vegetable, Eggplant (a member of the nightshade family along with tomatoes and potatoes) is actually a giant berry.
Western or globe eggplant is the most common and versatile variety, and you can find it year-round, though in most parts of the country, the peak season is late summer. Though it needs a little preparation, the reward is a succulent, silky treat. The globe eggplant's larger size enables you to get slices and chunks. It varies in size from 3/4 pound to 1-1/4 pounds, with dark purple skin. A fresh globe eggplant has pale pulp with a few noticeable seeds, which darken and become bitter as the eggplant matures. Eggplant with parts of dark, hardened pulp with lots of dark seeds will be a disappointment—these parts must be removed; otherwise, the flavor and the texture of the finished dish will suffer.
Eggplant varieties other than globe are worth seeking out. All have tender flesh and seeds and none need peeling (unless you're roasting and puréeing them for a dip). These varieties don't absorb as much oil as globe eggplant, nor are they bitter.
Italian eggplant is smaller than the globe variety. It's lobed, with dark purple skin and green leaves (though some varieties come in creamy white, soft lavender, bright purple, mottled, or striped). The Clara is white, has creamy, nutty nuances, and is best grilled. Rosa Bianca has a teardrop shape and a mottled white and lavender peel; it’s slightly sweet, with an almost fluffy texture, and it’s great on the grill, too. Also, try the bright purple Beatrice breaded and fried.
Chinese eggplant is elongated, slender, and has light purple skin. It's quick-cooking, which makes it a good candidate for stir-frying.
Japanese eggplant is also elongated, slender, and quick-cooking. This variety has dark purple skin. Its brownish leaves distinguish it from the Italian eggplant.
White eggplant is oval, with a beautiful eggshell-white hue; one look will tell you how eggplant earned its name. The flesh is especially creamy and is less bitter than darker-hued eggplant.
Southeast Asian eggplant is the size of a cherry tomato, green-striped or purple. It's quite bitter and best for pickling.
Small eggplants, also called baby or Indian eggplants, can be as tiny as a walnut or up to a few inches long. They cook quickly and, unlike other types of eggplant, rarely turn bitter, even with age. Use them for pickling or slice them in half and sauté. For braising, try Fairy Tale, which is sweet, tender, and marbled purple and white, and the oval-shaped Calliope, which has lavender and white stripes.
At the market, look for eggplant with smooth, shiny skin that's unwrinkled and free of brown spots, cuts, or bruises. The fruit should feel firm and spring back slightly when you touch it. Try to find an eggplant with a stem that looks moist, as if recently cut. Soft fruit with a dull peel is likely too mature and will taste bitter.
Globe eggplant, also called Black Beauty, whose flesh is especially spongelike, tends to soak up more oil than other varieties. If you've ever brushed a raw, unsalted slice with oil, you've probably noticed how readily the eggplant absorbed it. According to food scientist Harold McGee, salting eggplant flesh and letting it sit for about 30 minutes before cooking draws out water and helps collapse the air pockets in globe eggplant's spongy flesh. This makes the eggplant much less able to soak up lots of oil during cooking.
Eggplant is one vegetable for which slight undercooking will not work. It must be completely cooked through until it's meltingly soft, smooth, and creamy; only then will it be flavorful on its own, as well as receptive to the other flavors with which you'll blend it. Here are some great ways to prepare it:
Frying: This cooking method seems to throw people the most because of how much grease eggplant can soak up. If you're using globe eggplant, salt it and squeeze it dry; other varieties don't need salting. Be sure the oil is very hot and put the slices in the pan in one layer (if you crowd the pan, the eggplant will steam instead of fry and won't cook evenly). Turn often and adjust the heat to avoid burning until the slices are a rich brown color. Drain on paper towels.
Stir-frying: Quick-cooking Japanese and Chinese eggplant are the best candidates for stir-frying. Cut the eggplant into 1/2-inch cubes. When the oil is very hot, toss the cubes into the pan with a little salt and stir-fry until the eggplant is a rich brown color.
Grilling: As when frying, salt and dry the eggplant. Brush the slices with oil and grill over a medium-hot fire until soft and cooked through.
Char-roasting: Char-roasting gives eggplant deep, smoky flavor. The charred skin peels off easily. To start, pierce the eggplant with a skewer and cook it whole and unpeeled directly over a grill flame until the skin is blackened all over and the flesh is thoroughly soft, 15 to 20 minutes. Char-roasting can get messy, so if you're trying this over an indoor gas flame, line the burner trays with foil or try broiling the pierced eggplant instead. Peel off the blackened skin, drain the flesh in a colander, and squeeze out all the moisture.
Oven-roasting: As an alternative to char-roasting, pierce the eggplant in several places and roast it whole and unpeeled on a baking sheet at 350°F until it's quite soft and starting to collapse, almost an hour. Peel and drain it as you would for char-roasting.
It's best to use eggplant when it's very fresh, but it will keep for two or three days in the crisper drawer of the refrigerator. Be sure to remove any plastic wrapping before storing eggplant.