To Decorate:

5oz / 150g Dark chocolate
Lemon slices dipped in caster sugar


Whisk egg yolks with vanilla and sugar until pale and thick. Beat in the lemon juice, rind and yogurt.
Whip the cream into soft peaks, whisk whites until stiff. Fold whites and cream into lemon mixture.
Spoon into a container suitable for freezing and freeze for at least 5 hours.

Gently melt chocolate and pour as a sauce over the ice-cream servings. Decorate with lemon slices.