Bring the cream just to the boil with
the cardamom pods, then set aside to
infuse for 15 mins.
Keep one square of chocolate aside
and melt the rest gently in a large
bowl over a pan of barely simmering
water. Strain in the cream, then beat
with an electric whisk for a couple
of mins to thicken slightly. Pour into
pots, cover and chill for 4 hrs, or up to
2 days, until cold and set. Very finely
grate over the reserved square of white
chocolate to serve.