Wash 900g (2 lb) of Seville Oranges and cut them in half,
Squeeze out the juice and put it into a jug.remove the pips.
Remove the pips and the flesh from the oranges. I find a dessert spoon is a good tool for this.
Put the pips and flesh in a muslin or stockinette bag. I stretch the bag over a small bowl to help catch any extra juice.
Cut the orange halves into quarters.
Put half the orange pieces into the food processor. Process until the pieces are about the size of a small pea. Then process the remaining pieces.
Put all the processed peel into a large pan.
Squeeze the juice from one lemon and add to the pan. You can also chop the lemon halves in the food processor and include them in the marmalade if liked.
Put orange juice in a pan with 2300 millilitres (4 pints) of water.
Tie up the muslin bag with the pips and flesh inside and add to the pan. Leave a good long piece of string so you can easily lift it from the pan later.
Bring to the boil and simmer about 1½ hours until the peel is soft and liquid reduced by half.
Take out a bag of pips and squeeze out any liquid into a pan.
Stir in 1800 grams (7 cups) sugar over low heat until dissolved.
Boil rapidly for 15 minutes.
Then test for setting point using the wrinkle test. See notes.
Skim off any froth from the top of the marmalade. It's okay to eat this, but it will spoil the look of the marmalade in the jars. Just put it in a small dish and enjoy it on your toast.
Cool for 10 minutes in the pan, then stir well and ladle into warm, sterilised jars.
Cover, seal, and label the jars. Store in a cool dry place.
Serve Seville Orange Marmalade on hot buttered toast.