What we have here is a big success on Madison Street”Mainstreet”that stretch of resurgence running the backbone from Desplaines to Harlem Avenues. It’s been building from the early ’90s and it’s put a new, retro Forest Park into the “Suburbs” listing of Chicago travel books. You know about it, but not all about it.

Ankle your way up or down Mainstreet during the day and note the bright colors, design touches and overall improvements of businesses, boutiques, condos, stores, shops, galleries, restaurants and watering holes. Or cruise by at night to catch a live downtown with a history and personality all its own; one the shouts, “Stop here! Stick around! Spend a little time”and money!”

Typical of this growth and rebirth is a singular Italian cafe just a trifle south of Madison at 410 Circle. It’s called La Piazza, and its exterior is painted with colorful Tuscan landscapes. The restaurant is “upstairs” at street level because a comfortable jewel of a jazz lounge, La Piazza Sotto, is located beneath. So the place excels on two levels, with delicious food above complemented by delectable live jazz below”four nights a week.

Gaetano DiBenedetto is co-owner and chef. Still a young man, he lives in Oak Park and brings from his native Palermo a passion for serving Italian cuisine in the grand manner. You’ll also sense his pride in the music performed in the downstairs room. The man is a great lover of jazz, and it shows. He’s savvy to what pleases food lovers and jazz buffs, and he clearly enjoys his work”and especially the enjoyment of others.

For now, the aim of is to improve an already imaginative menu while impressing a growing clientele with an appetite for “mange” and music”such as the kind happening tomorrow night and every Thursday up to and including April 27″the Jackie Allen Quartet.

If a courtroom is for hearing, this foursome is for listening. Critics, reviewers, fans and other followers see Ms. Allen as the real thing, about to make her breakthrough. She had already recorded seven CDs when she recently signed a contract with Blue Note Records. Number eight, titled “Tangled,” will be released by this venerable label on May 23. On it, she demonstrates more clearly than ever her long-term, deep love of jazz, often infused with pop. Her father, a trad jazz musician, was an early influence, as was the strong music program offered at the University of Wisconsin.

Now dividing her time between Indiana and Oak Park, she and the rest of the quartet recently played The Green Mill while Patricia Barber was on tour. On tours of their own, the quartet has likewise done some traveling; from a music education exchange visit in Taiwan to an upcoming gig at Joe’s Pub in Manhattan on May 23 to celebrate the “Tangled” release. Then back to The Green Mill June 9 and 10.

Her solid jazz background sets fire to the impeccable players behind her. These people have names, and instruments, and hard-earned reputations of their own. They are: Laurence Hobgood, keyboard; Hans Sturm , bass and Dave Richeson, percussion. Rev. John Moulder, yet another Oak Parker, may well sit in on guitar at La Piazza.

The group is a free-flowing, yet “together” unit. Translation: they know where they’re going and how to get there”while enjoying the trip in the meantime. Those listening (not just hearing) will likewise enjoy the ride. Each member is a composer, and doubles (or triples) on his ax. Each anticipates, appreciates and subtlely complements the others”as a good quartet must do.

Just so you know, owner Gaetano does constantly book other jazz combos and groups on other evenings. Coming up, try this sampling: the The Alison Ruble Duo, John Moulder and Kelly Sill, Petra Van Nuis Duo, Typhanie Monique & Neal Alger, The Spider Saloff Trio. For more, go to www.piazzacafe.com or call 366-4010.

Finally, this man of parts also conducts well-attended cooking classes on the premises the last Saturday of every month. On alternate Saturdays he holds “fun and enjoyable” lessons in speaking Italian. Out of this comes a planned tour of Sicily in September. Just to keep busy, he’s working on a special Mother’s Day Jazz Brunch, Sunday, May 14.

La Piazza opened the jazz club in its previously vacant basement last December. The room seats 60 people, and expands on the “Jazz Wednesdays” that the restaurant offered prior to its opening. It was the last in a series of renovations for the popular restaurant, which also added a new private party room and wine cellar late last year.

The restaurant is open for dinner Monday through Thursday from 4:30 to 9:30 p.m. and Friday and Saturday from 4:30 to 10:30 p.m. It’s closed on Sundays.

The jazz club is open Wednesday and Thursday from 7:30 p.m. to midnight and Fri. and Saturday from 4:30 p.m. to 1 a.m.