Onion sauce

for 4 servings, for example, with bratwurst sausage, you need

• 2 medium onions, peeled and thinly sliced
• 1tbsp vegetable oil
• A good knob of butter
• 3tsp flour
• 1tsp tomato purée
• 1tsp Dijon mustard
• 100ml red wine
• 250ml beef stock
• Salt and freshly ground black pepper

To make the sauce

1. Heat the oil in a thick-bottomed pan and gently cook the onions for 8-10 minutes with a lid on until lightly coloured. You may need to add a splash of water if they are catching on the bottom of the pan.
2. Add the butter, flour and tomato purée and stir well over a low heat for a minute.
3. Add the mustard, stir well then
4. Gradually add the red wine, stirring to avoid lumps forming, before
5. Gradually adding the beef stock.
6. Season, bring to the boil and simmer gently for 20-25 minutes until the sauce has reduced by about two thirds and thickened. If the sauce is getting too thick, add a little water.
7. Remove from the heat and cover with a lid to keep warm.