Beat egg yolks in a small saucepan. Boil water in a large saucepan, remove from the heat, put it in a saucepan with the yolks and beat the egg yolks with a mixer until they brighten and will not increase in volume. Add fructose, lemon juice and grated lemon zest. Continue whisking until the mixture thickens. Remove from the pan with boiling water and leave to cool.

Separately whip the cream, carefully mix them with the cooled yolks. Pour the mixture into a plastic container or other easy to freeze container and freeze.