Use sterilised jars. Place a side plate into the freezer – you’ll use this to test the marmalade’s setting point.
Wash, halve and squeeze the ClemenGold mandarins and lemons into a large saucepan, retaining any seeds and pulp. Place pulp and seeds into a muslin cloth, tie up and place into the saucepan with the ClemenGold juice. Slice the ClemenGold peel into thin strips and add to the saucepan (add lemon peel if you prefer a bitter angle). Add the water and simmer over medium heat for 30-45 mins or until the rind has softened, taking care not to reduce the liquid too much.
Remove the muslin bag and strain all liquid into the saucepan. Add the sugar and bay leaves and simmer until the sugar has dissolved. Increase the heat to a boil and cook for 10-15 minutes at a time, checking the marmalade’s consistency by spooning a drop of liquid onto the chilled plate. Push the drop with your finger and if it crinkles, the marmalade is ready. If not, continue to boil the mixture. This can often take up to an hour.
Once the marmalade has set, leave to cool slightly before spooning into the glass jars and sealing tightly. Once opened, the marmalade will keep in the fridge for up to 3 months.