Thomas Keller, the driven genius of French Laundry, teams up with his freewheeling chef brother, Joseph, to cook a delicious meal in Napa Valley

Devotees book plane tickets to California and reserve tables months ahead for the chance to eat at Napa Valley's French Laundry, where Thomas Keller, arguably the best chef in America, puts his talents to work. Keller is famous for brilliant and whimsical fare, such as his savory ice cream cone--a cone-shaped cracker filled with sweet-onion crème fraîche and salmon tartare. Few but the most dedicated groupies know about Thomas's gifted chef brother, Joseph, who cooks under somewhat less media scrutiny at The Woodbox Inn in Nantucket, Rhode Island, preparing updated Provençal fare like herb-stuffed striped bass wrapped in beet greens with beet essence. Now the two brothers are teaming up to open a classic French bistro in Napa.

At first glance, the brothers could hardly be more different. Thomas, 42, is quiet and intense, a self-described worrywart. Joseph, 44, is an extrovert with a booming voice, shiny shaved head and tattoos. Still, the brothers share two qualities: a fierce work ethic and a discipline that comes with French training. As Thomas explains, "We're both believers in organization and preparation. Our mother taught us that no matter what you do, you do it the right way."

In fact their mother, Elizabeth, introduced the two to professional kitchens. Elizabeth, a restaurant manager, was anxious to return to work after having five sons and going through a divorce. Joseph and Thomas, who at ages eight and six were the youngest (sister Judy was born later), went with her. "Our afterschool activities had a lot to do with peeling vegetables," says Thomas. "Mom didn't believe in child labor laws." At home, Joseph prepared most of the family meals. "I would watch Graham Kerr and then run and make whatever he did," he recalls. Thomas didn't show much interest in cooking--"I was the one washing the dishes," he says--although Judy remembers at least one disastrous collaboration: "When Joseph was about 14, he and Thomas made French fries but forgot to take the plastic insert out of the Frialator. Do you know how bad plastic smells when it's burning? Well, it smells even worse when it's frying."

When Joseph was 10, he filled in for a chef who showed up drunk for work at one of his mother's restaurants; by 15, Joseph had landed at Petite Marmite in Palm Beach, Florida, a premier dining spot in the Seventies. After seven years, Joseph moved up to Nantucket, returning to Florida in the winters to cook; one memorable season he worked for a Saudi Arabian prince, who paid him with a suitcase full of cash. In 1988, Joseph walked into The Woodbox Inn and, except for winters spent working in France or snowboarding, he's been there ever since.

Thomas had a rather unusual reason for entering the restaurant business: "No job applications, no interviews, I'd just go to Mom." When he was 19, she hired him at The Palm Beach Yacht Club, and Joseph taught him to cook. After perfecting his technique in France, Thomas came to New York City at 27 and made his name at La Reserve and Rakel. He opened French Laundry in Yountville in 1994.

Now, for the first time in 20 years, the brothers will be collaborating in a restaurant. They're working on a bistro in Yountville, designed by Adam Tihany, that's due to open this month. In a departure from the American-accented cooking at the French Laundry and The Woodbox Inn, the bistro will feature classic French food. "It will be French French, not California French," says Thomas firmly. "We're talking blanquette de veau and tarte Tatin," adds Joseph.

To celebrate Team Keller, Joseph and Thomas recently took over the kitchen at the Napa Valley home and winery of their friends Jayson and Paige Pahlmeyer. Pahlmeyer winery, which sells to both French Laundry and The Woodbox Inn, gained pop-culture notoriety when its 1991 Chardonnay appeared as a key plot device in the Demi Moore film Disclosure.

For their dinner party, Thomas and Joseph planned a family-style meal. "It's comfort food," says Joseph, "the kind we like to eat when we're together now." Thomas passed around crostini, with toppings that included caramelized onions with cheese.

At the table, Thomas's meltingly tender braised short ribs with mustard sauce and stewed winter vegetables with sweet roasted shallots were the perfect match for Joseph's creamed tomato-studded potatoes. Joseph capped off the dinner with a light orange cake topped with a tangy rhubarb compote. Pahlmeyer wines flowed throughout.

At the end of the meal, the brothers took a moment to remember their mother, who passed away in 1982. "If Mom could see us now, she'd be so proud," says Joseph. "All the work she put into us has finally paid off."