½ ounce amaro (Thrasher uses Don Ciccio & Figli’s Luna Amara)
½ ounce gin (Thrasher uses Green Hat’s Spring/Summer seasonal gin)
½ ounce grapefruit reduction (recipe follows)
Garnish: Grapefruit peel
1 quart grapefruit juice
1 cup sugar
1 bay leaf
1 green cardamom pod
In a cocktail tin, combine first three ingredients with ice and shake. Strain into a large coupe, top with sparkling wine, and garnish with grapefruit peel.
In a pot over medium-high heat, slowly bring grapefruit juice to a boil. Add remaining ingredients and whisk until sugar has dissolved. Simmer until liquid is reduced by a third, then strain and cool.