Onion soup with Gruyère cheese.

Cook the onions until they turn brown and sweet. In a big pot, melt the butter and olive oil together on medium heat. Put the onions in and mix well. Cook for around 10 to 15 minutes until the ingredients are soft, then add the sugar.

Keep on cooking. Reduce the heat a little and cook the onions slowly, stirring from time to time, for around 30-40 minutes, until they turn a deep golden color and become caramelized. Be patient because this step is very important for the taste!

Include garlic and flour. Add the chopped garlic and cook for 2 more minutes. Add the flour little by little, stirring well to make the soup thicker, and cook for 1-2 minutes.

Remove the residue and let it cook slowly. Pour the wine into the pan to remove any cooked bits, stirring them in. Next, pour in the beef broth and add the bay leaf. Heat the soup until it starts to bubble gently, then lower the heat and let it cook for 20-30 minutes. Add salt and pepper according to your preference.