Bring the milk, cream, and ground cardamom seeds and crushed pods to the boil. Cover and allow to infuse for one hour.
Bring to the boil again.
In the meantime, combine the egg yolks, sugar and salt in a bowl using a whisk. When the cream has boiled, pour it over the egg yolks, whisking as you do so; then return the egg yolk mixture back into the pan.
Heat gently, mixing with a heatproof silicone spatula until the ice-cream base is 81°C - thick enough to coat the back of a spoon.
Pass through a coarse-sieve - you just want to remove the cardamom pods.
Immediately transfer into a heat-proof container. Clingfilm to the touch and refrigerate for 6 hours or overnight.
Churn the ice-cream according to the manufacturer’s instructions.