Homemade Seville Orange Marmalade

Scrub the oranges and cut in half. Squeeze the juice out and set aside. Slice the peel into thin slices and put in a bowl. Cover with 2-1/2 liters water and orange juice squeezed earlier. Leave to soak overnight or up to 24 hours.

Transfer the whole mixture into a large pot, or preserving pan if you have one. Bring to the boil and then simmer slowly until the peels are tender, about 2 hours. By this time the contents of the mixture should have reduced by 1/3.

Stir in the lemon juice and sugar and stir until the sugar has dissolved. Boil on a high heat for 35 minutes, until the temperature reaches 220F (using a candy thermometer). Remove from heat and allow to cool for 10 minutes. Pour into sterilised jars and seal. Will keep for up to 2 years.

To sterilise the jam jars, just run it through a dishwasher and allow to dry in a warm oven.