Prep 0 mins
Cook 45 mins
This marmalade can be stored in the refrigerator for up to one week
- 40 g butter
- 750 g onions, thinly sliced
- 200 g soft brown sugar
- 150 ml red wine vinegar
- 15 ml mustard seeds
- Heat butter in a large heavy-based pan and cook onion for 10 minutes, or until softened and lightly browned.
- Stir in remaining ingredients and cook, uncoverd, for a further 25 - 30 minutes, stirring occasionally, or until onions are lightly caramelized and very soft.
- Season to taste.
- Ladle into clean and hot jars and seal immediately.