Shake all the ingredients with ice, then strain into a coupe.
2.
Garnish with a brandied cherry.
Notes
What is Crème Yvette?
A liqueur made from four berry fruits—mûre, framboise, cassis, and fraise sauvage—blended with dried violet petals from Provence. It originated in 1890, was discontinued in 1969, then revived in 2009 by Cooper Spirits (the makers of St-Germain). It's technically still in production, but extremely difficult to find. The standard substitute is crème de violette (Rothman & Winter is widely available).
For the adventurous
Crème de violette lacks the complexity of Yvette, so some folks add a dash of crème de cassis. Start with a 4:1 violette:cassis mixture and adjust to taste.