Patricia Yeo

Big Leap: Creative director Patricia Yeo discusses a chicken recipe with executive chef Marc Bernard in the kitchen at Big Bowl. (Armando L. Sanchez/Chicago Tribune)

Last March, Big Bowl hosted an invitation-only dinner that doubled as an introduction to its star culinary hire, chef Patricia Yeo. She prepared a seven-course menu that featured beef heart crudo with pickled beets and citrus, and a three-tongue course of beef, lamb and duck.

Dishes starring heart and tongue seem at odds with a Chinese/Thai chain that serves 28,000 customers a week and counts kung pao chicken and pad thai among its best-sellers. One can't help but wonder if Yeo's hire was a sign that Big Bowl — in its 21st year as the flagship chain of the Lettuce Entertain You restaurant group — was veering its menu toward the more eclectic and adventurous.

The short answer is no. The longer answer poses a more complicated question: When a corporate chain hires a high-profile chef, how difficult is the balance of elevating its culinary verve without alienating mainstream sensibilities?

This age-old debate of art versus commerce continues on a 51/2-acre farm in Elburn, an hour's drive west of downtown Chicago in the Fox River Valley. Here, at Rustic Road Farm, Yeo strolls past honeybee hive boxes and wild cherry trees. She is bespectacled and diminutive, cutting less an authoritative kitchen figure than a laboratory scientist — Yeo, in fact, earned a doctorate from Princeton in biochemistry before pursuing cooking.

"This is the most relaxed I've ever been," said the Oregon-born Yeo in a British accent, the byproduct of her English boarding school upbringing. No longer managing a restaurant's day-to-day operation means Yeo has spare time for the first time in years — she volunteers at the Garfield Park Conservatory and plans to take Spanish lessons. "Right now," she said, "I speak 'kitchen Spanish.'"

The addition of Yeo to the Big Bowl team in January was indeed a big splash. An already-established name in San Francisco, New York and Boston, Yeo — her Chinese parents immigrated to Malaysia — is most recognizable from her appearance on the fourth season of "Top Chef Masters," the Bravo TV cooking competition in which she finished third runner-up.

Takashi Yagihashi, chef of his eponymous Bucktown restaurant and River North's Slurping Turtle, was a competitor against Yeo on "Top Chef Masters." When he heard she was moving to Chicago, his first thought was, "What the hell are you doing?"

"I was very surprised; I heard she was doing very well in Boston," Takashi said. "Now I think it's a very good move for her. She has a diversity of technique and experiences that she can bring to any kind of kitchen."

At Big Bowl, she effectively takes the position once held by Bruce Cost, the noted chef and Asian culinary historian who's now focusing on his ginger ale business. Yeo's title is "creative director," a catchall term that translates to conceiving new menu items at Big Bowl, tweaking existing dishes and eventually developing new restaurant concepts for Lettuce Entertain You.

How she describes her new job: "I get to play."

Rustic Road Farm looks as if it were slid sideways into the verdant cornfields of Kane County, surrounded on three sides by 10-foot-tall stalks. Several times a month Yeo travels here, a farm that Big Bowl executive chef Marc Bernard owns and at which he resides. Yeo calls Bernard her "work husband."

The farm was a major selling point in convincing Yeo to relocate from Boston to Chicago at age 53. Bernard offered to make this her culinary drawing board, where she could grow whatever rare and exotic produce she desired to stimulate creativity. The bigger draw was to do this without the middleman; the farm's output was enough to supply Big Bowl's four Chicago-area restaurants.

It was late July, the most gorgeous, cumulus cloud-fluffed day of the year. The wet spring was kind to the fertile soil in Elburn. Yeo walked through rows of kabocha squash, globe basil, pickling cucumbers and other herbs and produce grown at her request. She became animated showing off winged beans, indigenous to New Guinea, with a pod tasting like a hybrid of green beans and asparagus. These may make their way into a nightly special at Big Bowl's Gold Coast location, where Yeo works most days.

Having deep pockets for menu development is one benefit of working for a restaurant chain with eight locations. (Twenty total if you include Big Bowl Chinese Express, a quick-service concept. One opened inside O'Hare's Terminal 5 in May.) The trade-off is that even the most minute of changes can't be implemented overnight, and often not over weeks or months. Adding a new ingredient to a dish requires choreography on many levels: 1) finding a supplier who can fulfill orders on a large scale (say, 100 pounds of mandarin peel); 2) simultaneous deployment to its three markets around Chicago, Minneapolis and Washington, D.C.; and 3) explicit recipe instructions and training so the dish will taste consistent across all locations.

This doesn't even account for finding a recipe that will satisfy a customer base whose tastes differ from city to city.

At Big Bowl's Schaumburg restaurant, for example, beef dishes dominate sales. Customers in Lincolnshire prefer dishes with sweeter profiles. Minnesotans favor sweet and sour. At its Reston, Va., location, in suburban Washington, D.C., a large Indian customer base pushes the restaurant's spicy Thai green vegetable curry to the top of the charts. The most adventurous dishes, not surprisingly, are ordered at the two downtown Chicago restaurants, although less so at the River North store because it's frequented by more tourists.

When Big Bowl opened its first store in 1992, its original concept wasn't even Asian, but a gimmick of an inclusive meal served in oversize bowls (hummus, beef barley with short ribs, or a chicken soup with half of a roast chicken). Even with Lettuce founder Rich Melman's string of successes as a restaurateur, the idea was a flop.

Management noticed a pattern among dishes ordered: Asian soups were by far the best-sellers. Within six months, they made the decision to flip concepts. That the new Asian focus didn't necessitate a name change was fortuitous.

Just describing one's concept as "Asian" wasn't specific enough. Big Bowl President Dan McGowan said the management team held a three-day debate over whether the restaurant should be a Chinese and Thai restaurant, or an American restaurant serving Chinese and Thai food. They decided the latter had a better chance of success. It may seem like splitting hairs, but something as innocuous as background music — Western versus Far East — colors the experience. These days you might hear The Rolling Stones while sampling the pot stickers.

Today, Big Bowl has grown to become Lettuce Entertain You's largest franchise (in terms of number of locations). So why fix a model that's not broken?