Seville orange and vanilla bean marmalade

Method

1. Wash the oranges, scrubbing off any wax. Cut in half, then squeeze and reserve the juice. Halve the lemons, squeeze, then add the juice to the orange juice. Scoop the orange and lemon pips and any pulp from
2. the squeezer into the centre of a square of muslin, then tie with string. Cut the orange peel halves in two, then slice into strips (I like mine chunky). Put the peel, juice and muslin bag into a large bowl and add 2 litres cold water. Stir, cover and leave overnight or for up to 24 hours. This softens the peel and helps release the pectin, which is what sets the marmalade.
3. The next day, slit open the vanilla pod and scrape out the seeds onto a saucer. Cover and set aside. Cut each piece of pod in half. Pour the peel mixture into a preserving pan or very large, deep saucepan and add the vanilla pieces. Bring to the boil, then simmer, uncovered, for 1ó-2 hours until you can easily squash a piece of peel between two fingers.
4. Meanwhile put 2-3 saucers into the freezer. Heat the oven to 120°C/ fan100°C/gas ó. Wash the jam jars,
5. lids and jam funnel in hot soapy water, rinse well, then put into the oven to dry (this will sterilise them). Turn off the oven with the jars inside.
6. Fish out the muslin bag from the pan, drop it into a sieve, press out as much liquid as you can back into the pan, then discard. Add the sugar and stir over a low heat until dissolved. Increase the heat, bring to a rolling boil, then boil, without stirring, for 20 minutes. The bubbles should have subsided and the mixture will look glossy and heavy.
7. Keep checking the temperature using the thermometer. Once the marmalade reaches 102°C, see if it’s reached setting point (it can go as high as 104.5°C without spoiling). To test the set, slide the pan off the heat, spoon a blob of marmalade onto one of the cold saucers, then pop it back in the freezer for 2-3 minutes. If the blob wrinkles up when you push your finger through it, it’s at setting point. If not, return the pan to the heat, checking the temperature and testing again in 5 minutes.
8. Once setting point has been reached, take the pan off the heat, stir in the reserved vanilla seeds and leave for 20-30 minutes. Stir it to distribute the peel, then pour through the jam funnel into the warm jars, filling them to the top. If using cellophane, put waxed discs on top, or just seal with screw-top lids while still hot. Label and store in a cool, dark place.