The occassion was Mr. Niccolini's birthday—his 21st, if you believe the winking invite.

"Fifty-six, actually," noted the irreverent impresario, dressed dapperly as ever in a pinstriped suit and red tie.

So that's, what, 21 shots plus 35 shots?

"Absolutely, I think we should do that!" the good-humored Mr. Niccolini told the Daily Transom before turning to greet other guests.

WCBS-2 news anchor Maurice DuBois chatted with ladies by the bar, while Fashion Week organizer Fern Mallis snapped photos of the stylish crowd and gabbed about her new Bravo reality TV series, Fashion Show, hosted by Isaac Mizrahi.

The evening was more or less a prelude to the far bigger bash on Tuesday, May 5, when the illustrious restaurant itself turns 50. For real.

London's Financial Times recently attributed its longevity to "consistency, charisma and the peculiar nature of power and celebrity."

A full roster of prominent New Yorkers, including Blackstone Group's Pete Peterson, hotelier Jonathan Tisch, and domestic diva Martha Stewart, are lined up for a "classic comedy roast" of the owners, Mr. Niccolini and partner Alex von Bidder.

Yes, it's payback time for Mr. Niccolini, who seems to thrive on giving his power-broker guests a good ribbing from time to time.

"If you haven't been insulted by Julian, you are a nobody," as one financier by the unfortunate name of John Holmes recently told New York magazine.

“It could be bad," Mr. Niccolini predicted of the roast, in an interview with The Observer's Eight-Day Week. "It’s very easy to dig up dirt on people these days. You just Google people's names and there you have it. Thank God I've only been married once."