For the custard, pour the lactose free milk into a saucepan. Remove the cardamom seeds from their green pods.
Grind the seeds to a powder, add them to the lactose free milk with the saffron stamens and bring to the boil. Remove from the heat, cover with a lid and set aside for 20 minutes to infuse.
For the caramel, put the caster sugar in a small pan and then pour enough water to just cover it. Place the pan over a moderate heat and leave to boil, watching carefully, until walnut-brown in colour.
Preheat the oven to 150C/130C Fan/Gas 2. Pour the caramel into four China ramekins, twisting each one from side to side until the base of the dish is covered with a fine layer of caramel.
Put the kettle on to boil and return to the custard. Beat together the egg yolks, eggs and caster sugar.
Strain the infused lactose free milk through a sieve into a large jug to remove the cardamom and saffron. Pour the lactose free milk over the eggs and sugar and stir together.
Pour or ladle the mixture into the caramel-lined dishes. Lower them into a roasting tin, then place on the middle shelf of the oven. Pour enough boiling water from the kettle to come halfway up the sides of the dishes.
Bake the custards for 40 minutes, or until they are just set. They should quiver when gently shaken. Remove and leave to cool, then chill in the fridge for at least 2 hours.
To turn out, run a palette knife around the edge, place a small plate on top and turn the plate and ramekin over. Shake firmly and let the custard slide out.