Lemon Sorbet with Prosecco

Heat the sugar with 4 tablespoons of water in a small saucepan and bring to a clear syrup.

Remove the pan from the heat and stir the lemon juice and finely grated lemon zest into the warm syrup.

Rinse the lemon balm, pat it dry and chop it very finely.

Whip the egg white to soft peaks and gently fold it together with the chopped lemon balm into the lemon syrup.

Freeze the mixture in an ice cream maker until a creamy sorbet forms.

Without an ice cream maker, pour the mixture into a metal bowl and freeze for about 4 hours, stirring vigorously every 30–45 minutes.

To serve, place one scoop of sorbet in a tall glass and top up with well-chilled Prosecco.

Garnish with a lime slice and serve immediately.