The trick with this soup is to let the onions (many onions) first cook on very low heat, and then bake until golden brown. You must know yourself whether you subsequently use water, cube broth, or self-drawn beef broth or dark stock. But strangely enough, this soup is also made with water, which is nice for vegetarians (vegetable broth cube is also possible). Some recipes prescribe the use of flour to bind the soup, but the bread actually already has this function.
Peel the onions and cut into thin rings. Melt the butter in a pan with a thick bottom, do not let color. Add the onions, stir well so that all the rings are covered with butter, and let them cook for 15 minutes to half an hour with the lid on the pan. Occasionally check that the fire is not too high and scoop the onions again.
When the onion rings have softened, add wine and raise the heat. Allow the wine to evaporate and the onions to turn golden brown. Make sure that the onion does not burn, because then the taste becomes bitter. Onions have a sweet taste, if you want to strengthen them, add a teaspoon of sugar at the same time as the wine.
Add hot water or preheated broth to the onions, bring to the boil and let stand for another half an hour with the lid on the pan. Taste if you need salt and pepper, but remember that the cheese is also salty. If you are already preparing the soup in the morning or the day before, turn off the heat immediately after the broth or water has boiled. During the warming up just before gratinating, the onions stew enough. Grate the cheese on a coarse grater (do not use pre-grated cheese).
Rooster de stokbroodplakjes in de oven of het broodrooster lichtbruin.
