Blood Orange, Seville Orange & Lemon Marmalade

1. Place a sieve over a large pan. Remove the buttons (where the stems were attached) from the Seville and blood oranges and the lemons. Halve the oranges and juice them over the sieve into the pan (the sieve will catch any pips or bits of flesh). Halve and juice in the lemons. Scrape as much flesh, pips and white membranes out of the orange and lemon halves as you can – a teaspoon is good for this – and place them in a large piece of muslin cloth with any pips from the sieve. Tie this into a tight bag. Add the bag to the pan.

2. Slice the orange and lemon skins into quarters, then slice as much pith off as you like. Scoop this pith into another muslin square, tie into a bag and add to the pan. Slice the citrus skins to your preferred thickness and add them to the pan. Pour in 3 ltrs water, put a lid on the pan and bring to the boil. Turn the heat down and simmer for 2 hrs till the peel is tender. Take off the heat. Lift the bags out of the pan and set to one side in a bowl to cool for 1-2 hrs. This is so you can squeeze the pectin out later without burning your hands.

3. Sterilise your jam or preserving jars – you should make around 5-5½ ltrs marmalade. You can sterilise the jars by putting them through a dishwasher cycle, or washing them in hot, soapy water, rinsing them and then drying them in an oven set to 100°C/Fan 80°C/Gas ½. Put 4-5 side plates into the freezer to chill.

4. Gently squeeze the muslin bags over the pan, scraping any sticky liquid that comes out of the bag into the pan. This is the pectin, which will help the marmalade set. Try to get as much pectin into the pan as possible. Add the sugar to the pan and gently warm, stirring occasionally, till all the sugar has dissolved. Turn the heat up and bring the pan to the boil – keep your eye on it as the marmalade will froth and start to boil up. As soon as this happens, turn the heat down to stop it overboiling. If you have a sugar thermometer, the temperature you want to hit is 102°C.

5. Keep the marmalade at a rolling boil for 20 mins, then take it off the heat. Pour a spoonful of marmalade onto a chilled side plate, leave it for 1 min then press it with your finger. If it wrinkles when you press it, it's ready. If not, put the marmalade back on a medium heat and boil for a further 10 mins. Repeat the wrinkle test. The marmalade should be ready within 40-60 mins.

6. Use a tablespoon to skim any scum off the top of the marmalade. Ladle the marmalade into the sterilised jars, seal and label. The marmalade will keep for up to 1 year in the sealed jars.