- Heat your oven to 200C/180F/Gas 6. Put your thinly sliced onions into a roasting tray and drizzle over the olive oil, season and stir. Roast in the oven for 45 minutes, stirring a couple of times.
- Tip your onions into a saucepan and add the stock, mustard and Marmite. Bring to the boil and then turn down to a simmer for 15 minutes. Stir in parsley and serve with crusty bread.
Recipe from BBC Good Food Magazine.