French Onion Soup (Soupe à l'Oignon Gratinée)
By Middagsarkivet
- Medium
- 4 servings
French onion soup ended up on Nordic dinner tables the same way coq au vin and crème brûlée did: through the 1970s and 80s, when French bistro cooking was what you served people you wanted to impress. It stuck because it works. Four ingredients you already have, one of them is onions, and the result tastes like it took all day. It did take a while, but most of that is the pot doing the work.
In Denmark, Norway and Sweden it shows up as a first course at winter dinner parties, in small bowls before a roast, and at New Year's. The cheese on top is traditionally Gruyère. Norwegian Jarlsberg melts beautifully and is in most American supermarkets, as is Swiss, and either one does the job.
The only real rule is not to rush the onions. Twelve minutes of browning gives you onion soup. Forty-five gives you French onion soup. The color should be somewhere between mahogany and strong coffee before any liquid goes in.
How to make it
- 1
Start the onions
Melt the butter with the olive oil in a wide, heavy pot over medium heat. Add all the sliced onion with the salt. It will look like far too much; it cooks down to about a quarter of the volume. Stir to coat and cook, stirring now and then, until the onions have collapsed and released their liquid.
- 2
Caramelize
Stir in the sugar, lower the heat slightly, and keep cooking, stirring every few minutes and scraping the brown film off the bottom of the pot. The onions should go from pale gold to a deep, even brown. If the bottom threatens to burn, add a splash of water and scrape. Do not stop early.
- 3
Garlic and flour
Add the garlic and cook for 1 minute. Sprinkle over the flour and stir constantly for 2 minutes so it loses its raw taste and coats the onions.
- 4
Deglaze
Pour in the wine and scrape the bottom of the pot clean. Let it bubble until it has reduced by about half.
- 5
Simmer
Add the beef stock, thyme and bay leaf. Bring to a simmer, partly cover, and cook gently so the flavors come together. Fish out the bay leaf and thyme stems, stir in the red wine vinegar, and season with black pepper and more salt.
- 6
Toast the bread
While the soup simmers, arrange the baguette slices on a sheet pan and toast them in a 400°F (200°C) oven until dry and crisp on both sides, turning once. Dry bread is what keeps the toast from dissolving in the bowl.
- 7
Gratinée
Heat the broiler. Set four oven-safe bowls on a sheet pan and ladle in the hot soup, leaving an inch at the top. Float two toasts on each, cover them edge to edge with the Gruyère, and scatter the Parmesan over.
- 8
Broil and serve
Broil 4 to 6 inches from the element until the cheese is melted, bubbling and browned in spots. Watch it the whole time. Let the bowls stand for a minute before serving; they are extremely hot.
A couple of tips
If you are short on time, caramelize the onions a day ahead and refrigerate them. The soup then comes together in 30 minutes.
Grate the cheese yourself. Pre-shredded cheese is coated with starch and melts into a grainy layer instead of a smooth one.
No oven-safe bowls? Melt the cheese on the toasts on a sheet pan under the broiler and slide one onto each bowl of soup at the table.
What you need
- a wide, heavy pot or Dutch oven
- four oven-safe soup bowls
- a broiler
Serving
Serve as a starter before a winter roast, in small bowls, with a green salad in a sharp vinaigrette afterward to cut the richness. As a main, one large bowl per person with the rest of the baguette on the side is plenty.
Storing it
The soup itself keeps 4 days in the refrigerator in an airtight container and freezes for 3 months. Store it without the bread and cheese and gratinée fresh bowls when you serve it.
Nutrition per serving
| Calories | 670 kcal |
|---|---|
| Fat | 28 g |
| of which saturated | 14 g |
| Carbohydrates | 65 g |
| of which sugars | 17 g |
| Fiber | 7 g |
| Protein | 27 g |
| Salt | 3 g |
Questions and answers
- Can you freeze French onion soup?
- Yes, the soup base freezes well for up to 3 months. Freeze it without the bread and cheese, thaw overnight in the refrigerator, reheat, and gratinée fresh toasts on top.
- What can I use instead of Gruyère?
- Norwegian Jarlsberg or plain Swiss both melt well and are easy to find. Avoid anything pre-shredded, and skip cheddar, which breaks into oil under the broiler.
- Can I make it without wine?
- Replace the wine with 1 cup of extra beef stock plus an extra teaspoon of red wine vinegar added at the end. You lose a little acidity and depth, but the soup still works.
- Can I make it vegetarian?
- Use a dark vegetable or mushroom stock in place of the beef stock and add a teaspoon of soy sauce for depth. It is a different soup, but a good one.
- How far ahead can I make it for guests?
- Make the soup up to two days ahead and refrigerate it; the flavor improves. Toast the bread and broil the cheese just before serving.
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- 1 min 45 sec
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