Fill cocktail shaker with ice. Add tequila, blackcurrant liqueur, and ginger syrup. Shake until chilled. Strain into glass. Top with a float of ginger ale.

GINGER SYRUP RECIPE—peel and chop, 8 oz. fresh ginger. Add to non-reactive pan with 4C water and 2C sugar. Bring to a boil, reduce heat, simmer uncovered 45 min. Cool and strain. Store leftover syrup in airtight jar in refrigerator.