Shake gin, sugar, and lemon juice well with cracked ice in a chilled cocktail shaker. Strain into a Collins glass half-full of cracked ice. Top off with champagne.
- INGREDIENTS: 2 oz. (6 cl) London dry gin 1 tsp. superfine sugar 1/2 oz. (1 cl) Lemon juice 5 oz. (15 cl) Brut champagne