A nattily dressed man with a French accent posing as a job-seeking chef has robbed at least 10 Washington restaurants of a total of $20,000 to $30,000 since February, D.C. police reported yesterday.

The slender, muscular con artist in his mid-20s, who has a penchant for three-piece suits and a sophisticated, take-command manner, has hit dining spots ranging from a toney West End Italian restaurant to several popular singles bars and a Yummy Yogurt outlet.

In most cases, police say, he has talked his way into the business office of the establishment, pulled a large-caliber pistol, demanded large bills and then cooly walked away. Detectives say he has averaged $2,000 to $3,000 per robbery, but the amount has varied from as much as $9,000 in cash and $6,000 in checks at one place to only $200 cash at another.

Robbery squad detectives issued an artist's composite drawing of the suspect yesterday, showing a neatly groomed, mustachioed man. Detectives said the suspect, who on occasion speaks with what sounds like a French accent, may be from Haiti.

At least 10 restaurants and bars have been victimized since mid-February, according to Det. Gary Queen, who is coordinating the robbery squad effort to apprehend the suspect.

"The M.O. [modus operandi] has ben almost the same every time," Queen said. "This guy dresses very well. He's clean cut, nice looking . . . has a French accent and talks clearly."

Queen said that the suspect "comes in, asks for the manager and a job application as a chef. Usually, they take him into the office where the safe is located . . . . Then he pulls a gun and says something like, 'I don't want to hurt anyone . . . but I will if I have to.'

"He always asks for large bills. He doesn't want any small change. . . . He's very smooth and not nervous. After he gets the money, he doesn't run out. He walks out," Queen said.

Most of the holdups have occured in the early morning, presumably to intercept the restaurant manager before he takes the preceding day's revenue to the bank for deposit, he said.

Detectives described some of the holdups as "robbery by appointment." The suspect, they said, would call the restaurant in advance, make an appointment for a job interview, then show up a few days later and pull the robbery. They said he used a phony first name to identify himself.

Places hit have ranged from Archibald's, a restaurant featuring topless dancers at 1520 K St. NW, to DaVinci Ristorante, a posh Italian establishment at 2514 L St. NW. Others have included Flaps Rickenbacker's, 1207 19th St. NW; Samantha's, 1823 L. St. NW; The Bottom Line Saloon, 1716 I St. NW; Suzanne's, 1735 Connecticut Ave. NW; H. A. Winston's, 1333 New Hampshire Ave. NW; Beowulf Pub and Restaurant, 1112 20th St. NW, and Yummy Yogurt, 1337 F St. NW.

The most recent holdup occurred yesterday at the Beefeeders' 518 Restaurant, located at 518 10th St. NW. Detectives would not specify the amount of money taken.