Onion and Cheese Soup
300g white onions
2 tablespoons of oil
2 tablespoons of flour
1,5lt water or beef stock
8 croutons, fried in oil
50g grated Gruyère or Parmesan cheese
salt and pepper
Peel and finely slice the onions, then parboil them for 5 minutes in boiling water. Drain them and place them in a saucepan with the butter and the oil, let them brown evenly, then, still stirring, add the flour through a sieve, to avoid lumps forming. Add, little by little, the water or the stock and leave it to simmer for half an hour. Season with salt and pepper.
Beat the egg yolks. Put them in the tureen and slowly pour over the onion soup, mixing quickly.
Serve with the croutons and grated cheese.