French onion soup
Traditional French onion soup with toasted toast. Humble ingredients - onions, stock, bread, and cheese become luxurious through patient caramelization and a quick gratin under the broiler. The essence is sweet-savory depth balanced with a touch of acidity.
Ingredients:
- 7 pieces onion
- 20 grams butter
- 20 milliliters sunflower oil
- 2 tablespoons all-purpose flour
- 1 liter vegetable broth
- 1 pinch salt
- 1 pinch black pepper (ground)
Nutrition values (per 100 g):
| Energy | 40 kcal 169 kJ | |
|---|---|---|
| Protein | 0,8 g | |
| Carbohydrates | 5,0 g | |
| - of which sugars | 2,0 g | |
| Fat | 2,1 g | |
| - saturated fat | 0,7 g | |
| - trans fat | 0,0 g | |
| - monounsaturated fat | 0,5 g | |
| - polyunsaturated fat | 0,7 g | |
| - cholesterol | 2,3 mg | |
| Fiber | 0,8 g | |
| Salt | 0,1 g | |
All nutritional data is approximate and subject to variation based on ingredient choice, brand, and measured amounts.
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Nutrition values (for the whole recipe):
| Energy | 740 kcal 3 092 kJ | |
|---|---|---|
| Protein | 14,6 g | |
| Carbohydrates | 90,8 g | |
| - of which sugars | 36,9 g | |
| Fat | 37,7 g | |
| - saturated fat | 12,8 g | |
| - trans fat | 0,7 g | |
| - monounsaturated fat | 9,0 g | |
| - polyunsaturated fat | 13,4 g | |
| - cholesterol | 43 mg | |
| Fiber | 14,6 g | |
| Salt | 1,41 g | |
All nutritional data is approximate and subject to variation based on ingredient choice, brand, and measured amounts.
By clicking the table, you switch the view.
Recipe steps:
- Cut the onion into strips or rounds and fry it in butter and oil on a low flame.
- When the onions have softened and are not yet brown, add the flour and stir to make the flour fry nicely.
- Then add the broth, ideally vegetable, or beef. Add the broth cold and stirring constantly.
- Season with salt, pepper, bring to the boil and cook covered over a low heat for 30 minutes.
- Anyone who likes can add a little wine or brandy to the soup, it accentuates the taste of the soup (not adding at the end of the cooking, but about 10-15 minutes before the end to boil the alcohol).
- When serving, we use croutons that we have baked in the oven together with the cheese - we can even skip this step, but it would be a shame.
Ingredient choices:
- Onions: classic yellow; a 70/30 mix of yellow and sweet onions gives a rounder flavor. Slice 3–4 mm thick so they hold texture.
- Fat: butter plus a little oil prevents scorching and adds richness.
- Flour (optional): 1–2 tbsp for body.
- Stock: beef for a classic, robust profile; vegetable for a lighter, vegetarian take.
- Wine/brandy: a dry white wine or a splash of Cognac/brandy to deglaze and balance sweetness.
- Cheese: Gruyère, Comté, or Emmental for a good melt and nutty finish.
Technique cues:
- Slow caramelization: medium-low heat for 30 - 45 minutes to deep gold without burning.
- Deglaze: lift the fond with wine or a ladle of stock before adding the rest.
- Herbs and seasoning: bay leaf and thyme; grate a hint of nutmeg if you like. Salt at the end.
- Gratin: ladle into oven-safe crocks, top with a toasted baguette slice and cheese, and broil until bubbling.
Regional and seasonal spins:
- Lyonnaise style: extra attention to long caramelization, finished with Gruyère.
- Savoy twist: use Beaufort or Comté.
- Normandy: swap part of the wine for dry apple cider.
- Mushroom addition: sautéed mushrooms for earthiness.
Alternatives and dietary tweaks:
- Gluten-free: skip the flour and reduce further, use GF bread for croutons.
- Subtle smoke: a pinch of smoked paprika.
- Acidity check: finish with a few drops of sherry or apple cider vinegar if the soup skews sweet.
Croutons and cheese:
- Day-old baguette toasts better and absorbs without collapsing.
- Rub with garlic, cover with cheese, and broil to a molten cap that traps aroma.
Troubleshooting:
- Too sweet: add acidity (wine/vinegar), a touch more salt, or black pepper.
- Bitter notes: heat was too high; lower the flame and deglaze.
- Too thin: simmer uncovered to reduce.
- Too thick: loosen with stock or water.
Storage:
- The base (without croutons and cheese) keeps 3 days refrigerated and freezes well.
- Adjust with stock when reheating.
