The only trick you need with this one is patience: you really want to let the onions cook and brown, because that will make them soft and sweet rather than crunchy and overpowering.
Ingredients (for four portions, but make more if you want to make sure you have extras):
- 4 large onions or 6 medium onions. Ideally a mixture of yellow and red onions is best, but you can use whatever you have.
- 1 tablespoon of olive oil
- 1-2 tablespoons of butter
- 2 tablespoons of flour (you can use cornstarch or any gluten free flour as well)
- 1 cup of white wine
- 2-3 cups of vegetable stock
- salt and pepper
- for topping: croutons, grated cheese, or cheesy toasts (see below)
1. Slice the onions into fairly thin rings or strands.
2. In a large pot over medium heat, heat the olive oil and butter together until the butter is melted, but not browned.
3. Add the onions and cook, stirring occasionally, until the onions are very soft. You may need to control the heat, to make sure that the onions don't fry up and burn, but rather "sweat" and become soft and golden-brown. This can take some time, so be patient.
4. When the onions are very soft and golden-brown add the flour and stir for about 30 seconds. Then add the wine and the vegetable stock. If the soup looks too thick, you can add some water or more stock now, but you can also wait until later.
5. Season the soup with salt and pepper, cover the pot and simmer for about 20-30 minutes to let the flavors combine.
Serve with toppings.
To make cheesy toast:
Slice baguette into one inch (2.5 cm) thick slices. Place on a baking tin. On each slice place a little bit of butter and top with grated cheese. Place in a hot oven or under the broiler for a few minutes, until the cheese is melted and the toasts are crisp.