How to cook
Cool the glasses or bowls for the sorbet in the refrigerator. Grate the rinds of the lemons. Squeeze out the juice from the lemons and put the gelatin in it. Once it swells, dissolve it in a water bath on low heat.
Add the sugar and stir. Cool the mixture to room temperature. Add the champagne, stir and leave in the freezer for 3 hours.
Take out from the freezer, blend in a blender and leave for another 3 hours in the freezer. Beat the egg white to snow.
Take the sorbet out of the freezer and add the egg white and white wine. Mix everything. Distribute into the cooled glasses and sprinkle with lemon zest. Serve immediately.