Combine plenty of Vanilla Sugar with a pinch of cinnamon on a shallow plate and mix.Using a wedge of lemon, wet the rims of 2 coupe glasses. Dip or roll the wet-rimmed glasses in the sugar mixture until it sticks to the glass rim. Shake off any excess, then set aside while you make the cocktail.

Add all ingredients except Prosecco into a shaker with plenty of ice and shake until well-chilled.

Strain into coupe glasses, top with Prosecco, and garnish with a sage leaf before serving.