If your fruit is waxed then you will need to wash off the wax from the skin of the fruit first by giving it a light scrub. Cut the oranges, lemons and grapefruit into quarters then with very sharp knife remove the skin from the pith and the flesh.
Cut the peel lengthways again. You might need to cut the lemon peel once, the orange peel twice more and the grapefruit peel three times more to get even sized pieces. Then cut widthways into short thin strips.
Weigh the peel, you should have around 450g.
Place the peel into a stainless steel saucepan with the cold water then bring to the boil. Turn the heat low and simmer for 1 hour.
Remove from the heat and set a sieve over a large bowl. Pour the contents of the saucepan through the sieve, set aside the peel for one moment and weigh out the cooking water.
Pour 1140ml of the cooking water back into the saucepan with 900g of the sugar. If you don’t have enough cooking water then just top up with tap water. Bring the sugar and water to a gentle boil and simmer for 10 minutes until the sugar has dissolved.
Pour the sugar syrup over the peel, cover and leave the peel to soak for 24 hours.
Strain the syrup into a large saucepan and return the peel to the bowl.
Add the remaining 450g of sugar to the saucepan. Bring to a boil, then turn down to simmer for a couple of minutes making sure the sugar has completely dissolved.
Pour the syrup back over the peel, cover and leave for another 24 hours.
Pour the peel and syrup into a large saucepan. Bring to a boil, then turn the heat down to simmer for 30 minutes.
Pour everything back into the bowl, cover and leave the peel to soak for four final days.
Drain the fruit, place on a fine wire rack and leave in a sterile dry place until no longer sticky, such as a turned-off oven. Although leave a note on the oven that it is not to be used. The mixed peel can take as long as seven days to completely dry. The best way to store the mixed peel afterwards is in sterilised glass jars and should keep for at least a couple of months.
Recipe adapted from the Reader's Digest 'The Cook's Scrapbook' Ed. John Palmer