When Arvid Brown and his team were creating the cocktail list at Portland, Maine’s Room for Improvement, he thought back to advice he received from an early bar mentor: “You can never get mad at a Cosmo. No matter how good your house cocktails are, you’re always going to make Cosmos since people will always order them.” So, he thought, Why don’t we make our Cosmo one of our flagship drinks?

The intention was to appeal not only to the customer who orders Cosmos at every bar, but also to “nerdy cocktail friends who might never ordinarily call for a Cosmo,” says Brown. That meant rethinking each ingredient. “We looked at what it is that people like about it: It’s pink, it’s served up, it’s citrusy, it’s refreshing and it’s got a little tartness,” Brown says. “We tried to reengineer those flavors with more craft ingredients.”

The vodka was easy: “St. George Spirits makes a really excellent but very affordable citrus vodka,” Brown says, citing its nuanced flavor, which includes bergamot. For the orange liqueur, Brown ordered more than a half-dozen types and tried them in various 50/50 blends. The winning combo marries Pierre Ferrand Dry Curaçao, which has a Cognac base for added depth, and Clément Créole Shrubb, which brings richness and spice to the glass. The blend also helps solve what Brown sees as an issue with Cosmopolitans—they tend to be thin. “We thought about how to give it roundness and body, and Creole Shrubb was that ingredient.”

Brown knew he needed something more complex than juice for the cranberry component. After trying various syrups and macerations, he settled on blending equal parts cranberries, sugar and water in a Vitamix until smooth, then fine-straining the mixture and adding a measure of Campari. This “cranpari” cordial is cranberry-forward, “but the Campari adds depth and bitterness and amps up the color of the drink,” according to Brown. The final touch is a few drops of saline solution, which Brown likes adding to shaken sours. “When we were doing tastings, we made one with salt and one without and hands-down we liked it better with the salt. It amplifies the flavors.”

With its sneakily complex flavor profile, the Cosmopolitan fits right into the easygoing vibe at Room for Improvement, where every drink, no matter how common, is executed at a high level without becoming too fussy. The bar’s dive-y ambience and lowbrow food menu—everyone is eating Maine red snapper hot dogs and crunching cheese balls—may make it a surprising spot to find some of the best cocktails in town. But it makes sense that this dichotomy was Brown’s plan all along. Like everything at Room for Improvement, the cranpari Cosmo “turns your expectations on your head.”