Melt the chocolate in a heatproof bowl over a pan of barely simmering water, making sure the bowl doesn't touch the water.

Split the vanilla bean lengthwise and scrape out the seeds with the back of a knife. Then crush the cardamom pods with the flat of the blade of the knife.

Place the milk in a separate pan and heat to just under boiling point, then add the sugar, vanilla seeds, and cardamom pods. Stir until the sugar is dissolved.

Using a strainer to catch the crushed cardamom pods, pour the milk into the melted chocolate and stir. Add the cream, stir well, and leave to cool at room temperature.

Once cool, pour into an ice-cream maker and churn following the manufacturer's instructions. Keep in the freezer until required.