500 g (5 oz) panforte di Siena
150 ml (5 fl oz) Vin Santo
900 ml (1.1/2 pints) double cream
225 ml (7.1/2 fl oz) milk
2 vanilla pods
8 organic egg yolks
175 g (6 oz) caster sugar
For six
Chop three-quarters of the panforte into small pieces in a food processor or by hand. Place in a bowl and pour over the Vin Santo.
In a thick-bottomed saucepan, combine the cream and milk. Using a knife, scrape the vanilla seeds out of the pods into the mixture. Gently heat until the mixture almost reaches boiling point.
Beat the egg yolks and sugar together until pale and thick. Pour a little of the hot cream mixture into the egg yolks and stir. Return this mixture to the remainder of the hot cream and stir over a low heat, cooking it very gently. The mixture will gradually thicken, but do not allow it to boil. At this point remove from the heat, pour into a bowl and allow to cool.
When cool, stir in the panforte mixture. Pour into an ice-cream maker and churn until frozen, or freeze in a suitable container, stirring every now and again. Serve with a thin wedge of the remaining panforte.