Put the strawberry quarters, sugar, and lemon juice in a food processor or blender; process the mixture briefly so that the berries are finely chopped but not pureed. Add the Champagne, pouring it slowly against the inside of the bowl to keep it from frothing. Blend quickly to retain as much effervescence as possible. Pour the mixture into a shallow nonreactive metal pan and put in the freezer. Every 20 minutes, take it out and stir or break it up with a fork until there is no juice left, just sludge (1-1/2 to 2 hours). Scoop into dessert glasses. Garnish with reserved strawberries, and serve with a glass of chilled Champagne.

they were scooped out with a melon baller) in a champagne glass.