This is the recipe I inherited from my grandmother, and to me it is exactly how a good onion soup should taste.
French Onion Soup
serves 4
Ingredients
4 large onions (about 1kg)
50g butter or olive oil
1-2 cloves of garlic, minced
1/2 ts (teaspoon) black pepper
1/4 ts sugar
20g flour (about 2.5 ts)
2 dl dry white wine (sauvignon blanc, or another nice one you like)
0.8 liter chicken or vegetable stock
a baguette or other light bread (ciabatta, pide, etc)
8 Ts (table spoon) grated cheese, pref. Gouda or Gruyere.
Slice the onions in rings or half rings.
Take a big pot suitable for soup. Melt the butter and sweat the onions for about 10 minutes on medium fire, while stirring well. Add the garlic and sweat for 5 more minutes.
Add the sugar, flour and grinded pepper and braise it for 5 more minutes.
Preheat the oven (grill) on 200 degrees.
Now add the wine to the onion mixture, enjoy the aroma for a moment, then add the chicken stock. Leave it to simmer on low heat for about 15 minutes, preferably you want your soup to be only just boiling.
Taste and add salt/pepper to your liking.
Cut your baguette/other kind of bread into slices (about 4 cm each). Pour the warm soup into nice bowls, put a slice of bread in the soup, take the grated cheese and sprinkle it over the bread and soup. If you are using a softer kind of bread, you could toast it before putting in the soup.
Now put the bowls under the preheated grill and melt the cheese untill it is golden brown (5-7 minutes, depending on the grill). Be careful when lifting the bowls out, as they might be hot. Serve straight away
Often with soup, the taste is even better the day after making it. I normally make the onion soup the evening before, which means I can just fire my oven, heat the soup, put it into bowls, melt the cheese and tuck away. Also great when you have guests as it saves your time in the kitchen.
For a slightly different flavour, and some more complexity, you can use some different kinds of onions: great white onions, banana onions, red onions, shallots, anything really, or just what you happen to have in stock. And to add some more warmth it is nice to add some (moderately hot, deseeded & sliced) chili pepper when sweating the onions.
