French onion soup with Gruyére toasts

Method

1. Peel the onions and slice thinly. Melt the butter in a saucepan. Add the onion and cook on a low heat for about 40-60 minutes with the lid off, stirring frequently – the onions should be dark and well caramelised but not burnt.

2. Add the stock, season with salt and pepper, bring to the boil and cook for a further 10 minutes. Taste and correct seasoning.

3. Ladle into deep soup bowls, put a piece of toasted baguette covered with grated cheese on top of each one.  Pop under the grill until the cheese melts and turns golden.

4. Serve immediately but beware – it will be very hot.

5. Note: Hold your nerve, the onions must be very well caramelised otherwise the soup will be too weak and sweet.