Writer Sally Horchow belongs to not one but two cooking clubs in Los Angeles, a center of cooking-club mania. She describes a memorable session with a guest instructor, charismatic chef Govind Armstrong of L.A.'s Table 8.

I'm a sucker for group activities. In the past I've shuttled between book clubs and writing groups, aerobics classes and improv comedy workshops. Had I been old enough in the 1970s, I would surely have been on the Tupperware party circuit. So it's not surprising that, as a passionate cook, I have joined the latest trend: I belong to not one, but two cooking clubs.

Alternatively dubbed dinner clubs or supper clubs, among other names, these groups bring together friends to cook, eat and—most of all—learn. The two cooking clubs I belong to in Los Angeles are very different. One, called the Saucy Spoons, was founded two years ago by Ellen Rose, owner of the Cook's Library, a popular cookbook store here. The 16 members are mostly food pros, including cookbook author Neelam Batra; Stacie Hunt, a partner in the wine store Du Vin; and Joan McNamara of Joan's on Third, a restaurant and take-out food shop that's practically an L.A. institution. Every month we test out an intriguing cookbook—The Zuni Café Cookbook by Judy Rodgers, for example, or The Arrows Cookbook by Clark Frasier and Mark Gaier. We each pick a recipe and prepare as much of it at home as possible, finishing it when we arrive at the host's house. Then we dish about what we liked and didn't like. One time, for example, we all loved a crumb cake recipe so much, Joan started serving a version of it at her store.

My other cooking club is a lot less formal—we've never even given it a name—but it's equally rewarding. It too started about two years ago, with a group of about 10 girlfriends, all thirtysomething Angelenos working in industries from television casting to landscape design, who were already regularly calling each other with cooking questions and swapping recipes. Sometimes the more experienced cooks prepare and teach a menu to the rest of the group. Other gatherings are potluck and themed (Hors d'Oeuvres Night, for example, or Thanksgiving Prep). We've also taken a wine-and-cheese pairing class together and gone on field trips to sample a new restaurant.

To take our collective cooking expertise up a notch, our group recently invited 35-year-old chef Govind Armstrong of L.A.'s hot Table 8 to give us a lesson in my outdoor kitchen. Raised in Los Angeles and on the Caribbean coast of Costa Rica, Armstrong started his career as a 13-year-old intern at Spago and trained with internationally acclaimed chefs like Juan Mari Arzak of Arzak in San Sebastián, Spain, and Joachim Splichal of Patina in Los Angeles, before becoming co-chef (with Ben Ford, son of actor Harrison) at Los Angeles's Chadwick in 2000. Since then, he's designed the bar menu at RokBar in Hollywood, which he co-owns with Tommy Lee of Mötley Crüe and other backers; and he's opening a second Table 8 this winter at the new Regent South Beach Hotel in Miami.

When Armstrong arrives, he greets everyone with a hug, then tosses his long dreadlocks over his shoulder and gets to work making a round of pomegranate margaritas. As we gather around the outdoor bar, Armstrong kicks off the first demonstration: a quick way to cure duck to make prosciutto for a watercress salad. First he scores a breast and brushes it with maple syrup, then he applies a rub of salt, sugar and herbs. "Put a good amount on both sides," he tells us. "The salt is penetrating and doing its thing, and after 48 hours, it will give the meat a darker, richer color and more flavor."

Next Armstrong gives a lesson on how to cut a winter squash. Whether preparing a kabocha, red kuri or hubbard, he explains, the starting point is turning the gourd on its side and chopping off the stem. Still holding the squash on its side, he stabs it with the tip of the knife, pushes the knife partway in and pulls it down. He turns the squash around and repeats this action on the opposite side, which splits the squash open. Then he bakes the halves with butter and brown sugar, cuts them into wedges and sprinkles them with thyme-roasted chestnuts and pomegranate molasses.

Everyone moves in closer for the slicing of a gorgeous rack of Berkshire pork, which Armstrong has brined and then roasted. As he cuts it into chops, Armstrong hands out samples of the deliciously moist meat, which he will later serve with stewed onion puree and crispy sage leaves. He explains why cooking a whole rack is easier than roasting individual chops: "If you're making nine different chops, you have to check the temperature of each one," he says. "Besides, there's something a little more dramatic about having a big ol' honkin' rack of pork on the table and carving it up there."

For the final lesson, Armstrong reveals a tray of Krispy Kremes that he'll use in a dessert he calls Coffee & Doughnuts, a bread pudding he serves at RokBar with a dollop of coffee-flavored whipped cream. "I thought it would go over well in a bar," he says, submerging the sugar-glazed doughnuts in rich custard before baking.

Demonstration over, our cooking club adjourns to the upstairs terrace to sample the finished dishes. We settle in quickly around the table, and Armstrong steps out of the fray of passing and serving. "You guys seem to know what you're doing now," he says.

Govind Armstrong's popular restaurant Table 8 is located at 7661 Melrose Ave., Los Angeles; 323-782-8258.

Sally Horchow has written for the New York Times, Vanity Fair and dailycandy.com.