Serves: Makes about 450ml
Cook: 50 min
3 large Onions, thinly sliced
3 garlic cloves, thinly sliced
3 tbsp Olive oil
1 tsp black mustard seeds
1 tsp Coriander seeds
3 tbsp red wine vinegar
4 tbsp dark muscovado sugar
salt and fresh ground black pepper
1. Tip the onions into a large, heavy-based pan and add the garlic, olive oil, mustard and coriander seeds. Stir well to combine and then cook gently over a low heat for 20 minutes, stirring occasionally.
2. Stir in the vinegar and sugar and continue to cook for another 10-20 minutes until the onions have become completely translucent and the marmalade well reduced, stirring occasionally. Stir in 4 tablespoons of water and continue to cook for another 10 minutes until the marmalade is well thickened and slightly sticky. Season to taste.
3. If you are not planning on using the onion marmalade immediately, wash a Kilner jar or a couple of jam jars, rinse thoroughly, then dry in a warm oven. Stand them upside down on a clean tea towel.
4. If you are using jam jars, fill them, then cover the marmalade with a disc of waxed paper while still hot or else completely cold, then seal with a dampened disc of clear plastic, secure with an elastic band and screw back on their tops. Simply secure and close a Kilner jar in the normal way. Label and store in a cool, dark place for up to 2 months, then use as required. Otherwise transfer the marmalade into a serving bowl, cover with clingfilm and chill until needed.