I found this recipe on liquor.com.

St-Germain elderflower liqueur, dry white wine, club soda⁣
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No history (again) because this drink uses St-Germain and it has only been around since 2007.⁣
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Since I added St-Germain to my bar, lots of people have suggested mixing it with wine or sparkling wine. I can see why, it is tasty. And in a glass with a bunch of ice and the bubbles from the club soda makes it a lovely summer treat.⁣