Tommy’s Margarita. Denny’s.

Those two things wouldn’t normally show up in the same paragraph. The first is a liquid article of faith for serious bartenders the world over: a mix of 100 percent agave tequila, fresh lime juice and agave syrup that is considered a purer expression of the margarita, one that showcases the spirit.

The second is a restaurant chain famous for serving pancakes day and night.

Yet when Denny’s opened its first New York City restaurant on Aug. 29, a stone’s throw from City Hall, there on the menu was Tommy’s Margarita. Alongside it was a Dark and Stormy, made with rum infused with a Chinese five-spice mix; a draft cocktail called the Manhattan Cream Soda, made of bourbon, vermouth, maple syrup, vanilla and acid phosphate; and a Vesper, just in case James Bond walked in.

There’s also a healthy selection of spirits available by the glass. As one bewildered customer said the other night, “I didn’t expect Denny’s to be the spot for whiskey.”

Denny’s isn’t the first restaurant chain to try to co-opt modern mixology, but its attempt may be the most sophisticated to date. Remove the company logo, and the cocktail menu wouldn’t look out of place at some of the more casual cocktail bars that have opened lately in Brooklyn and Lower Manhattan. The taste of the drinks would pass muster as well.

The list is the work of Mike Capoferri, a Los Angeles-based bartender and bar consultant who was recommended to the management by a mutual friend. The franchise owners knew they wanted a bar, but didn’t know what kind. Capoferri suggested craft cocktails.

“There are other Denny’s with bars,” he said, “but none like ours.” In keeping with the chain’s reputation as a “value brand,” he said, he was determined to keep the prices low (the costliest drink is $11) and the concoctions fairly simple. “I look at it as Craft Cocktails 101. It’s the basics.”

Talk of value notwithstanding, the item that has drawn the most attention is the Grand Cru Slam; $300 gets you a Grand Slam breakfast for two (eggs, pancakes, sausage and such), a bottle of Dom Pérignon and a “bartender high-five.”

The pairing was a bit of an accident. In February, the franchise owners invited neighbors to a meeting, hoping to allay their fears about the coming restaurant. Mr. Capoferri created a mock-up of the bar menu, listing the Grand Cru Slam. “I put that on there as a kind of a joke,” he said, “and people loved it.”

He had so little confidence it would sell that when the restaurant opened, he had only one bottle of Dom Pérignon in stock. Within its first week, that Denny’s went through a case of the Champagne.

Capoferri said the bar menu would change from time to time, adding new drinks and draft beer. But, given the “breakfast and brunch friendly” food menu (there’s a good reason prosecco is on tap), he knows there are limits to what he can offer.

He said, “I can’t put a Negroni variation on there.”