Place the chocolate in a large, heatproof bowl and set a sieve over the top.

Heat the milk, sugar, salt and allspice in a pan until almost simmering. Meanwhile, whisk together the egg yolks in a large bowl until smooth. Gradually add the hot milk to the egg yolks, whisking constantly.

Return the mixture to the pan and place over a medium-low heat; stir constantly until it has thickened enough to coat the back of a spoon, do not let it boil.

Pour the hot custard through the sieve onto the white chocolate then stir until the chocolate has melted, mix in the cream. Taste and add more allspice if required.

Cover the bowl, allow to cool then refrigerate until completely cold. Stir until smooth then churn in an ice cream maker according to the manufacturers directions; transfer to a lidded container and freeze for a couple of hours until firm.