In KFC's innermost sanctuary, where its chicken creations are hatched, the racks of spices and sauces stretch along a wall, within easy reach for a chef to zest up the latest concoction.

Perhaps mixed among the batches of ingredients are the secret 11 herbs and spices blended by Colonel Harland Sanders more than a half-century ago that launched the fast-food empire.

Now, from KFC's test kitchens, cooks whip up new ways to serve chicken to people in a hurry and hungry for newfangled fast food.

"It's innovate or die," said Nadine Brewer, whose job as KFC's vice president of consumer research is to keep up with those eating habits.

From one of KFC's main test kitchens, nestled securely within company headquarters, chefs secretly create dishes featuring chicken covered with glazes, slapped between buns or wrapped in soft tortilla shells.

For the chefs, the culinary experimentation includes a dash of persistence, a pinch of patience — plus a healthy appetite.

"You have to have a passion for food," said Bryan Scherer, KFC's director of product development. "You have to love to cook and love to eat. We go home very full every day."

The creative process reaches its zenith three times a year at "chefs' councils," an assembly of KFC executives, franchisees and food experts. Chefs spend the day whipping up creations as the gathering assesses — between bites — the various batters, sauces and toppings.

"I think you eat your body weight in food that day," Brewer said.

The company averages one to three new menu items each year, Brewer said. For every item that makes it to KFC's menu, countless others are shelved after rounds of taste tests and consumer surveys.

The company has spread its wings beyond the traditional buckets of Kentucky Fried Chicken that made it famous. KFC has successfully pitched chicken wings, chicken strips and twister sandwiches to customers looking for variety.

That has helped make KFC the world's largest chicken restaurant chain with $4.4 billion in worldwide sales in 2000. The Louisville-based company, part of Tricon Global Restaurants Inc., has more than 10,000 outlets in 80 countries serving nearly 10 million customers daily. Tricon's fast-food empire also includes Pizza Hut and Taco Bell.

Scherer and Holly Rackowski, two fixtures in the test kitchen, were at the forefront of one of KFC's newest additions, a wrap with chicken, lettuce and crunchy noodles. The two bring considerable experience to the table.

Scherer has 22 years' experience in product development and spent several years in culinary arts training. Rackowski, a senior product development scientist, has spent five years with KFC and has a bachelor's degree in nutrition and dietetics and a master's degree in food science.

The Crispy Caesar Twister is an outgrowth of the KFC's successful original twister sandwich that debuted in the mid-'90s. The latest sandwich features two chicken strips, lettuce, parmesan cheese, pepper mayonnaise sauce and crispy rice noodles tucked in a soft tortilla shell.

In just six months, the sandwich was transformed from a test-kitchen concept to a menu item introduced in July at KFC restaurants nationwide.

Rackowski recalled one intense day of experimentation in the kitchen with a group of taste-testers. Each batch elicited opinions on improving the sandwich. Then it was back to the oven to cook more chicken, tinker with the sauce or vary portions of lettuce, cheese and noodles.

"We probably made 30 different sandwiches," Rackowski said.

It was Scherer who suggested sprinkling in the noodles to add some crunch to the sandwich. "I wanted a crouton-like texture but didn't want to put bulky croutons into the sandwich," Scherer said.

Scherer hit on the idea while grocery shopping for his family. He spotted the hard noodles, and soon a package was in the test kitchen.

All that remained was to refine the Caesar sauce a bit. Once that was done, the sandwich was headed toward hungry customers.

Months later, Rackowski saw a commercial for the sandwich appear on a television screen at her fitness center.

"It's one of the best rewards, seeing your product on the market," Rackowski said.

By that time, Rackowski and others in KFC's test kitchen were tinkering with the latest batch of ideas to dress up chicken.

Brewer said the possibilities are almost limitless.

"You look at cookbooks and there are a gazillion things you can do with chicken," Brewer said.