step 1
Sterilise the jars and lids in a pot of boiling water, or in an oven at 160C, and keep warm until ready to use.
step 2
Wash the chillies and remove any stalks.
step 3
Put the chillies in a food processor and pulse until they are finely chopped.
step 4
Add the sugar, cider vinegar, lemon juice and salt to a large pan over low heat without stirring, until the sugar has dissolved.
step 5
Add the chopped chillies to the pan. Bring to a boil and simmer for 15 minutes.
step 6
Increase heat to a rolling boil (around 105C). Add pectin, stirring constantly for one minute, then remove pan from the heat.
step 7
Ladle jam into the jars, leaving 6mm headspace, wipe any trace of jam off the rim with a paper towel and screw on lids.
step 8
Submerge the sealed jars elevated on a rack, or upturned saucer, in a large pot of boiling water. Once the water has returned to a full boil, leave for 10 minutes, then remove jars from water. Leave overnight in a cool place for the jam to set.
step 9
Store in a dark cool place for up to a year. Once opened, store in the fridge and use within one month.