Orange marmalade (fine cut)

• 3lb (1.4 kg) bitter oranges
• juice of 2 lemons

Scrub the oranges and pick off the small disc at the stalk end. Halve the oranges and squeeze out juice and pips. Cut the peel in quarters and cut away any thick white pith. Finely shred the peel. Coarsely chop the white pith and tie in a loose muslin bag along with pulp and pips. Put shredded peel, orange and lemon juice, muslin bag of pith, pulp and pips, and water into a preserving pan. Brin