Beat the sugar, egg yolks and vanilla essence together with a whisk until the mixture becomes pale, creamy and double in volume. In another bowl, whisk the egg whites to stiff peaks and also whip half of the cream in another bowl to soft peaks. Put the ricotta, lemon zest, egg yolks mixture in a bowl and gently fold everything together lightly. Fold in the whipped cream followed by the egg whites. Grease the parfait moulds and fill with this mixture. Even out the top and freeze until set. Meanwhile, prepare the fruit to be served on the side by heating together the sugar, raisins, coloured peppers, vinegar together in a small pan with a little water for 5-10 minutes. Allow to cool down completely before serving with the frozen parfait.