Bok Choy describes a large group of leafy, often white-stemmed vegetables, in the Brassica family often called cruciferous vegetables.  Nutrients called phytochemicals found in cruciferous vegetables provide health protection by decreasing the effects of cancer causing chemicals.  The most active and important of these phytochemicals is called diindolylmethane (DIM) and plays a role in balancing hormones.  (Other Brassicas that offer these same benefits include broccoli, Brussels sprouts, cabbage, kale and cauliflower.)

Mature bok choy is the full grown, leggy vegetable, which resembles a bunch of wide-stalked celery with long, full leaves. Choose bunches with firm white stalks and crisp spruce green leaves.  Bok choy can be used raw in salads, in a stir-fry or as a cooked vegetable.

Preparing  Bok Choy:  Trim the base.  Discard blemished leaves.  Separate stalks as you would celery.  Rinse thoroughly, checking base of stems for grit.  Slice leaves from stalks (the tiny heart can be left whole).  Cut wide stems lengthwise, then into diagonals.  Tear leaves into bite-size or cut into chiffonade.

Collards, a variety of cabbage, are an ancient plant of Eurasian origin that represents the oldest cultivated form of cabbage.  Often confused with kale, collards are thick-leaved, dense and cabbagey in flavor.  Collards peak season is January through April, but are available year-round in most markets.  Look for crisp green leaves with no evidence of yellowing.  Collards are an excellent source of vitamins A and C, as well as calcium and iron.

Preparing Collards:  Small leaves can be left whole or sliced into 1/2 inch pieces.  If collards are large, strip stems from leaves and discard stems.  Stack leaves and halve lengthwise, then cut into 1/2 inch strips.  Dunk leaves into a water bath and lift out, so that the grit sinks.  Repeat until the sink no longer feels sandy.  (Do not be tempted to stop at one washing!)

Kales are most abundant, flavorful and tender during the coldest months, although they are available most of the year. Kale is one of the open-leafed, darker green members of the cabbage family and is slightly stronger in flavor than collard greens.  Choose deep-colored bunches with moist, small-to-medium leaves.  As with all greens, avoid dried, browned or yellowed leaves.

Preparing Kale:  Kale leaves that are very small need not be stripped from the stems; cut off the base of the stems then slice leaves to suit and wash.  For larger leaves remove stems then drop into plenty of water and wash vigorously, drain.

Cooking Kale: Kale can be steamed, blanched, sautéed or added to soups.  For a stronger flavor, braise in a stock.  For milder flavor, steam kale and drizzle with lemon juice or balsamic vinegar and a pinch of sea salt.

Mustard Greens have peppery dark green leaves with a pungent mustard flavor.  They are a popular ingredient in soul food, second only to collard greens.  According to Elizabeth Schneider, author of Vegetables from Amaranth to Zucchini, taste is of utmost importance when choosing mustards.  “Every batch, every bunch of mustard varies, from as mild as bok choy to searingly sharp, from semisweet to indelibly bitter,” she writes.

Mustard greens can be stored for up to one week if refrigerated in a ventilated plastic bag.  Wash greens just before cooking.  Mustard greens can be cut into ribbons and stirred into soup or stewed with starchy vegetables and pureed.  In addition, mustard greens can be cooked along with potatoes, beans or grains.

As a member of the cruciferous family, mustards are an excellent source of vitamins A and C, thiamine and riboflavin.

Swiss chard, a member of the beet family, is best from spring through the fall. Spruce up winter soups and stews with chopped greens, add tender, young greens to salads or sauté mature greens with garlic and top off with a drizzle of olive oil and balsamic vinegar.  The variety with dark green leaves and reddish stalks has a stronger flavor than that with lighter leaves and stalks.  Ruby chard has a bright red stalk and a deep red-tinged leaf.  As with beets and their greens, the stalks of chard have a mellow flavor and naturally complement the earthy robust leaves.  In Portugal and Spain they are sautéed together in garlic-infused olive oil.  Yum!