Salted duck eggs.

Khai khem is a duck egg that has been cured in salt for a few weeks, either in a strong brine or packed in a salty paste of clay or rice husk ash. The salt slowly works through the shell. By the end the white is soft and quite salty, and the yolk has turned firm, round and orange-red, with a little oil around its edge. A small piece goes a long way, which is why one egg often feeds the whole table.

Ways to use it

• Boil, cut in half through the shell, and eat with plain rice porridge in the morning.
• Make yam khai khem: chopped salted egg tossed with shallot, chilli, lime juice and a little sugar.
• Mash the cooked yolk and stir it into a stir-fry with prawns, squid or crab until it coats them in a sandy, golden sauce.
• Add sliced egg to a clear soup with winter melon or greens, and season the broth lightly since the egg brings salt.
• Use the yolk in baking, such as mooncakes and pastries.

Most salted eggs are sold raw and need cooking. Put them in cold water, bring it to the boil and simmer for about 10 minutes.

Storing it

Keep the eggs in a cool spot out of the sun and go by the date on the pack. Once boiled, keep them in the fridge and use them within a few days.

Where it comes from

Grown to certified organic standards. The certificate for each lot is shown when you trace your pack.

Every pack will carry a lot code. Enter it on the Trace your pack page and you will see the farms in that lot, the packing date and the certificate.