This quantity makes about six 450g jars. You can make marmalade with any citrus fruits or a mixture of several, but thick-skinned, pip-packed Seville oranges make a classic preserve with a bittersweet flavour. Seville oranges are in season for a just few weeks in January. We reckon hunkering down for a few hours of prepping and cooking is an excellent way of spending a January Sunday afternoon. And your kitchen will smell wonderful.
Ingredients
1kg Seville oranges
1 lemon
2.5 litres water
2kg granulated sugar

Cut the lemon and oranges in half and squeeze the juice out. Put the juice and water in the pan and place the pips and any bits of pith on a muslin over a bowl.
Cut the orange and lemon peel into quarters then slice into fine shreds (you can use a food processor, but this will cut the peel into pieces rather than shreds). Add the shreds to the water and any pips or spare pith onto the muslin.
Tie up the muslin to form a pouch, and tie this to the handle of the pan so the bag hangs in the water. Turn on the heat and simmer the mix gently, uncovered, for 2 hours or so, until the peel is completely soft. To test this, pick out a thicker piece and press it between your thumb and finger. It should feel soft when you rub it and look slightly see-through.
Next, put three small plates in the fridge or freezer to chill.
Remove the bag of pips, squeeze out the sticky jelly and add it to the pan. Pour the sugar into the pan and heat very gently, stirring, until it is all dissolved.
Then turn up the heat to bring the mixture to a fast boil. After 15 mins, spoon a little of the marmalade onto one of the cold plates from the fridge, and chill the plate for a minute. Then push the mixture with your finger: if it wrinkles, it’s set. If not, continue to boil and test every few minutes or so until it does wrinkle. Remove the pan from the heat and leave to settle for 20 minutes or so.
In the meantime, sterilise your jars by boiling in water or putting in a medium oven for 10 minutes.
Ladle the marmalade into the warm jars and put the lids on while still hot. Store in a cool, dark place. It should keep for up to a year.