Place all ingredients except cranberries in a large heavy-based saucepan, then gently heat, stirring, until the sugar dissolves. Bring to the boil, then reduce heat and simmer, uncovered, for about 50 mins, stirring regularly until the apples and onions are tender, the mixture has thickened and no watery juice remains.
Add the cranberries, then cook for a further 10 mins or so until just softened but not burst.
Spoon the hot chutney into sterilised jars and seal.
Store unopened in a cool, dark place. The chutney will keep for up to 6 months.