The key to this drink—beyond the unusual pairing of grapefruit and parsley—is the grapefruit syrup. Luckily, it’s super duper easy to make grapefruit syrup since it’s just simmering some grapefruit peel in sugar and water for a few minutes.

A big upside to this drink is its flexibility, it works as a cocktail or a mocktail—so making a batch for a mix of drinkers and non-drinkers is easy. Also, it works with what clear alcohol you like: vodka, gin, white rum, silver tequila, mezcal… whichever you prefer or have on hand is going to work. And if like so many of us you’re a fan of an Aperol spritz… use Aperol!

Serves 4

Prep time: 10 minutes

Cook time: 10 minutes

Use a sharp paring knife to remove strips of zest—that’s the colorful outside of the peel, with as little of the bitter white pith attached—from about 1/2 of 1 of the grapefruit. But the strips with the sugar and 1/2 cup water in a small saucepan. Bring the mixture to a boil over high heat, reduce heat to maintain a steady simmer until the mixture thickens a bit, about 10 minutes. Drain into a small metal bowl, reserving the zest, and let cool.

Set aside 4 parsley leaves or double-leaves to use as a garnish. Put the rest of the leaves in the bottom of a heavy glass or cocktail shaker and muddle them—just gentle crush them with a muddler or the end of a wooden spoon.

Stir in the grapefruit syrup. Cut the grapefruits in half and juice 3 of the halves into the mixture. Cut 4 slices to use as garnish from the final half and then juice the rest of it into the mixture.

Fill 4 old-fashioned or high ball glass with ice. Divide the grapefruit-parsley mixture between them. Add alcohol to the glasses for people who want cocktails. Top with seltzer, give a good stir, and garnish each glass with a grapefruit slice and a mini-sprig of parsley.