“Tom and Jerry has been in my heart every since I worked at Blackbird for Dale,” recalled Audrey Saunders, proprietor of the bar. She was referring to the renowned barman Dale DeGroff, who ran the bar program at the short-lived Midtown restaurant Blackbird in 1999. “That was my first experience with it. He said, ‘O.K., we’re putting out the Tom and Jerry for Christmas.’ I said, ‘What’s Tom and Jerry?’ I got the history and the accouterments. The first time he put it out on the bar, it was, oh, my God, the magic of Christmas.”

For the recipe she serves at Pegu, Ms. Saunders cut back on the sugar. “I felt it could be cloying,” she said. “My addition was the Angostura bitters. It helps dry it down and give it the structure it needs.” She also adds vanilla. “It makes a huge difference.”

(There is no set date for the drink’s arrival at Pegu Club, but Ms. Saunders said it would probably make its debut before Christmas, “unless its 50 degrees out — so hard to gauge these days.” The Tom and Jerry schedule at Dram, a Williamsburg bar, is similarly sketchy, the drink popping up on selective snowy days and New Year’s Eve.)

One bar that was ahead of the curve is the Elizabeth Street saloon that calls itself Tom & Jerry’s. It opened in 1993, and owes its name to its vast collection of Tom and Jerry bowls, which were donated by Joe Wilfer, a printer and Wisconsin native who collected them. The tall, many-shelved back bar was built expressly to accommodate them.

Its name notwithstanding, Tom & Jerry’s serves the drink only once a year, at an annual holiday party for which a number of Mr. Wilfer’s Wisconsin friends make the trip. Joanna James, an owner of the bar, has no interest in making the drink more often. “It’s kind of labor intensive,” she said.

Also, she doesn’t like the stuff. “It’s too rich and heavy for me,” she said, laughing. “But I can see why people would love it.”