Pernelle

Select and pre-chill a highball glass.

Prepare a garnish of lemon zest twist and a rosemary sprig.

Shake the vodka, elderflower liqueur, Poire William eau-de-vie, and freshly squeezed lemon juice with ice.

Strain the mixture into the highball glass filled with crushed ice.

Top with soda water and briefly stir.

Express the lemon zest twist over the cocktail and use it as a garnish.

Garnish with a rosemary sprig.