Wash and scrub the fruits under warm water, and pat them dry. Try to use unwaxed fruits, if they are available.
Top and tail the citrus, then cut in half lengthwise. Slice the fruits into half-moons, the thickness of each slice will depend on your personal taste. Try to catch all the juices that may escape from the fruits.
Place the sliced fruits and resulting juice in a large pan, add cold water to just barely cover. Bring up to a boil, then leave to simmer vigorously for 30 minutes.
Add 1kg of caster, reserving the rest for later.
Split the vanilla beans in half, and add to the pot.
Bring back to a boil; when the water comes to a rumbling boil, turn the heat down so that everything comes to a slow simmer, cover with a lid and leaves to cook out for 45 minutes to an hour.
Check that the peels have becomes tender, and taste for sweetness. If the marmalade is too bitter, gradually add more sugar until you are happy with the level of sweetness.
Turn up the heat so that the marmalade comes to a brisk simmer, and leave to cook for a further 30 minutes, uncovered, stirring it occasionally so as to avoid any sticking.
When the jam is done, remover the vanilla pods, pot up in sterilised jars, seal, and leave to cool in a draft-free place.
Kept in a cool cupboard, unopened jars of marmalade should keep for one year. Refrigerate once the jar is opened.
«The vanilla can be omitted or substituted with another spice, such as cinnamon stick or cardamom pods. This marmalade is ready to eat straight away, however, it does improve greatly with some maturation. Its peak flavour is between 2 and 6 months.»
While the best orange marmalade is made with Seville oranges, any citrus can be turned into a lovely homemade spread. The fruits in this recipe can be substituted for any citrus you like, but do try to always include lemons as they contain the most pectin.