He sits at the counter near the rear of the Florida Avenue Grill, contemplating a plate of green beans and spareribs with murder in his eye. In this neighborhood, they call this kind of grub soul food, but Rob van Bavel, 22, has never seen it in his life. He's from Wagenberg, Holland, and this is his first meal in the land of the free and home of the brave.

"I love the United States," he says, digging into his spareribs like an expert.

How long has he been here?

"A half hour."

Van Bavel is a Dutch jazzman, and yesterday's unscheduled visit to a real live American soul food joint is one of the small perks he earned by becoming one of the 22 semifinalists for the first Thelonious Monk International Jazz Piano Competition.

The annual competition, sponsored by the Smithsonian Resident Associate Program, the Beethoven Society of Washington and the Washington-based Thelonious Monk Center for Jazz Studies (scheduled to open in 1990), is being held at the Baird Auditorium of the National Museum of Natural History at 10th Street and Constitution Avenue. The first round was held yesterday afternoon. This afternoon's continuation of the semifinals begins at 1 p.m, and tonight, five finalists face off at 7:30. Both events are open to the public.

The contest features what its organizers are calling some of the finest young jazz pianists in the world -- from as far away as Australia and as close as Gaithersburg -- vying for $18,000 in prize money. It is one of the largest and most prestigious competitions of its type, and organizers hope it will focus attention on the second-class-citizen status of jazz in the United States as well as help attract the $14 million needed to get the Monk Center going.

"It's now in vogue to call jazz 'America's classical music,' " says Thelonious Monk Jr., son of the great composer-pianist who died in 1982. "I reject that notion. I say jazz is 'classy' music. The notion of this music being associated with dark, smoky taverns has got to go."

If yesterday's competition was any indication, the link with smoke-filled, good-time juke joints is fading fast. The event was held in what might be considered antiseptic circumstances. The contestants were asked to perform three selections -- two Thelonious Monk compositions and one of their choice. They were given a strict time limit and were interrupted by the judges if they ran over. The audience of roughly 100 was instructed not to clap before or after the performances.

The result was a curious silence and grimness about the whole process -- though the $10,000 first prize, of course, is serious business indeed. There was also an ironic scarcity of black pianists. Only three of the 22 contestants are black, according to Monk Center executive director Tom Carter, and in an age where New York City alone boasts young talents like Kenny Kirkland, Mulgrew Miller, James Williams and George Caldwell (to name a few), it seemed odd that more were not present. Monk Jr. points out that organizers spread the word through the media as best they could given time constraints, and notes that pianists were selected on the basis of the tapes they submitted. "We picked the competitors on merit. There were no pictures, no references to ethnic background," he says.

Not that the contest was lacking in credibility. The panel of judges included some of the most renowned jazz statesmen alive -- pianists Barry Harris, Sir Roland Hanna and Hank Jones among them, as well as Roger Kellaway and Dado Moroni. They sat in the rear of the auditorium, stern and unsmiling, as the young pianists marched across the stage one by one, going through Thelonious Monk compositions with as much verve and skill as they could muster.

Which was plenty. Monk Jr. remarked during a break in the proceeding that he felt fortunate he wasn't a judge, and he had good cause. Each contestant demonstrated great technical efficiency, dancing through a variety of styles in the jazz tradition. As a whole, the pianists tended, as many young pianists do, to focus on technique -- with long classical runs more appropriate to Bach than bop. The great Monk himself, whose technique was often underestimated, was a genius in the use of space in his solos.

Notable among yesterday's efforts were fine performances by Harry Appelman, a New England Conservatory graduate student, and Alva Chester Nelson III, currently a pianist with the Boys Choir of Harlem, who took a break from touring to perform a sensitive, beautifully understated version of the Monk standard "Round Midnight."

But no one performer truly outshone the others. "We're all winners," said Nelson after the performance. "I'm not sure I like the idea of competition, but it's about furthering the spirit of Afro-American music. The turn-on is playing for the judges like Roland Hanna and Barry Harris. I'm impressed that this music is being accepted by those who didn't accept it years ago."

And he was right. To watch Arthur Dutkiewicz of Poland march through "Round Midnight" and Frank Chastenier of West Germany swing through "Evidence" is to know how pervasive and extraordinary Monk's influence has been. Though he was better known than most jazzmen in his later years, Monk still joins a long list of jazz musicians who are honored more in death than in life, and the great composer himself might be tickled to know that such a grand competition is transpiring in his name and honor.

"The script is already written," says Monk Jr. "We all have a part. We're looking forward to educating a whole new generation of musicians. We have to keep the basic principles of the art intact and nurture the artists."

The semifinal competition resumes this afternoon with Philadelphia whiz kid Joey De Francesco, a 16-year-old who recently recorded an album with saxophonist Grover Washington. Other contestants include Marcus Roberts, the pianist of the Wynton Marsalis Quartet, Australian Fiona Bicket, Japanese pianist Kuni Mikami and Robert Lyle, musical director for singer Anita Baker.