1. Peel onions and cut into 5mm thick slices

2. Pour olive oil into a large pan or skillet and heat to medium

3. Add onions to pan and stir well to ensure that all slices are covered with oil

4. Turn the heat down slightly and cover the pan, stirring every few minutes to prevent them burning and sticking to the pan base.

5. After about 20 minutes the onions will start to change to a yellowy brown colour.

6. Add the rosemary, bay leaves and salt and pepper and continue to cook, stirring every few minutes for another 20 minutes

9. Now add the rest of the ingredients – red wine, red wine vinegar, balsamic vinegar and brown sugar. Stir in and simmer for about 20 minutes – it may take slightly longer or less for the liquid the reduce .

10. Whilst the liquid is reducing – place the glass jars into a warm oven, this will sterilize them and prevent the glass breaking when the hot mixture is added .

11. The marmalade is ready once most of the liquid has disappeared and the mix look sticky .

12. Remove the rosemary and bay leaves from the mixture

13. Take the hot jars from the oven and spoon the mixture into them leaving a centimeter or two gap at the top.

14.Place a greaseproof cap on top of the mixture and press down before screwing on the lid .

17. Leave the mixture to sit in the jars for 2-3 weeks before eating – in order for the acidity to reduce and the full flavours to emerge .