Lemon Shred Marmalade

• 5 large lemons
• 1 grapefruit
• 6 pints/3 litres

Peel the lemons thinly and cut the peel in fine shreds. Cover the peel with 1 pint/500ml water and simmer with the lid on until the peel is soft. Take all the white pith off the lemons and cut up the flesh. Peel the grapefruit and cut the flesh into pieces. Put the fruit in a pan with the remaining water, cover and boil gently for 1½ hours until the fruit is soft. Drain the lemon shreds and add