300 g watermelon rind
30-90 g water
90-150 g caster sugar
1-2 lemons or limes, juice only
1 pinch of salt
5 cm ginger, coarsely chopped
Remove all green outer skin and all red flesh from the watermelon rind. Using a food processor, reduce the white rind to very small pieces, but do not puree. Put with water in a saucepan. Bring to a boil, cover and cook for 15-20 minutes. Add lemon juice, sugar, salt and ginger. Bring to a boil again, cover and simmer for 45 minutes. Uncover and cook for a few minutes more, until the liquid thickens like syrup. Remove the ginger. Fill into jars and seal.