2 tbsp olive oil
450g/1lb button onions
25g/1oz/2 tbsp butter
450g/1lb button mushrooms
3 large field mushrooms, sliced
2 garlic cloves, crushed
1 tbsp plain (all-purpose) flour
175ml/6fl oz/¾ cup red wine
250ml/9fl oz/1 cup hot vegetable stock
1 tbsp tomato paste
50g/2oz/½ cup walnut halves
1 bouquet garni
salt and ground black pepper
1 Preheat the oven to 170°C/325°F/Gas 3.
2 Heat 1 tbsp oil in a large frying pan, add the button onions and cook for 5 minutes, stirring, until golden brown. Remove and transfer to a casserole.
3 Add the remaining oil and the butter to the pan, then add the mushrooms and cook for 3 minutes, until starting to brown. Add the garlic and cook for 2 minutes.
4 Stir in the flour and then add the wine, hot stock, tomato paste and walnuts. Stir well and add the bouquet garni. Bring to the boil and then transfer to the casserole.
5 Cover the casserole and cook in the oven for 1 hour. Season to taste with salt and pepper.
6 Serve in shallow bowls with mashed potato.