Kathy Casey likes making her own Limoncello, the sweet Italian lemon liqueur, for this drink. (You can watch a video at liquidkitchen.tv.) Pallini Limoncello, which is widely available, also works well here.
In a cocktail shaker, muddle the clementine. Add ice and the gin, Limoncello, lemon juice and honey syrup and shake well. Strain into a chilled coupe, top with the Champagne and garnish with the lemon twist and orange wheel.