1½kg sweet oranges
1 tsp butter
1. Wash the fruit, remove the stem ends and cut into quarters. Put in a jam pan with the water, bring to a simmer, cover the pan and cook the fruit for 1 hour or until the peel is tender when pierced with a fork.
2. Drain the fruit and return the juice to the preserving pan. Once the fruit has cooled a little use a spoon to scrape the pulp away from the skins and add the pulp to the juice in the pan. Simmer for 10 minutes – this extracts the pectin from flesh and pips – while you cut the soft peel into fine strips.
3. Strain the liquid, discard the pulp and return the strips of peel to the pan. Bring this to a simmer and add the sugar gradually, stirring until the sugar has dissolved.
4. Bring the marmalade to a fast, rolling boil, stirring often, and boil for 5–6 minutes.
5. Remove from the heat and test the marmalade for a set. When the marmalade reaches setting point stir in the butter to remove any froth and let stand for 10 minutes. The marmalade will thicken a little as it cools and the strips of peel will not rise to the top.
6. Pour the marmalade into sterilised jars and cover tightly.