SaveFrench Onion Soup
Deeply caramelized onions in rich beef broth, topped with a crusty gratin of melted Gruyère.
Edited by Brian Kaplan·Last updated April 12, 2026
Servings
Est. total: $12.00 · $3.00/serving
Cost estimates are approximate and vary by location, store, season, and brand. Actual prices may differ.
Ingredients
- 4 large yellow onions (thinly sliced)
- 3 tbsp unsalted butter
- 1 tbsp olive oil
- 1 tsp sugar
- 1 tsp salt
- 1 tbsp all-purpose flour
- 1/2 cup dry white wine
- 6 cup beef broth
- 4 sprigs fresh thyme
- 1 piece bay leaf
- 1/2 tsp black pepper
- 2 tbsp cognac or sherry
- 1 tsp sherry vinegar (finishing acid)
- 4 thick slices French bread (day-old works great)
- 1 piece garlic clove (halved, for rubbing bread)
- 1 tsp fresh thyme leaves (for gratin topping)
- 2 cup Gruyère cheese (shredded)
Instructions
- 1
Melt butter with olive oil in a large heavy-bottomed pot over medium heat. Add sliced onions and salt. Cook, stirring occasionally, for 10 minutes until onions are soft and starting to release liquid.
3 tbsp unsalted butter1 tbsp olive oil4 large yellow onions1 tsp salt - 2
Reduce heat to medium-low. Add sugar. Continue cooking 35-45 minutes, stirring every 5 minutes, until onions are deep golden brown and caramelized. Deglaze with splashes of water if they start to stick.
1 tsp sugarReal caramelized onions take 40+ minutes. There are no shortcuts — low and slow is the only way.
- 3
Sprinkle flour over onions and stir 1 minute. Add cognac or sherry and carefully ignite or let it cook off for 30 seconds. Pour in white wine and scrape up any browned bits. Cook until wine is almost evaporated. Add beef broth, thyme, bay leaf, and pepper. Simmer 20 minutes. Finish with sherry vinegar for brightness.
1 tbsp all-purpose flour2 tbsp cognac or sherry1/2 cup dry white wine6 cup beef broth4 sprigs fresh thyme1 piece bay leaf1/2 tsp black pepper1 tsp sherry vinegar - 4
Preheat broiler. Rub each bread slice with the cut side of a halved garlic clove. Ladle soup into oven-safe bowls set on a baking sheet. Float a garlic-rubbed bread slice on each. Pile Gruyère on top and scatter fresh thyme leaves over the cheese. Broil 3-5 minutes until cheese is bubbly and golden brown. Watch carefully.
4 thick slices French bread1 piece garlic clove2 cup Gruyère cheese1 tsp fresh thyme leavesKeep the oven door cracked and watch constantly — broilers go from golden to burnt in seconds.
Pairs With
Cru Beaujolais like Morgon or Fleurie
Light, fruity red that doesn't overpower the delicate onion sweetness
Trappist-style dark ale
Caramel and dark fruit notes echo the caramelized onions
White wine with a splash of crème de cassis
The classic French aperitif — sweet and fruity
Make It Yours
Tap a dietary need to see exactly what to swap.
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Cooking Soundtrack
Edith Piaf, jazz manouche, and the kind of music that makes butter taste like love.
Nutrition
Per serving. Estimated values. Not a substitute for professional dietary advice.
Tips
- •The sugar helps kickstart caramelization but isn't strictly necessary.
- •Day-old bread holds up better than fresh — it won't dissolve into the soup.
Substitutions
- Gruyère cheese → Swiss cheese or provolone
- dry white wine → dry sherry
- beef broth → mix of beef and chicken broth
Leftovers
Store soup (without bread and cheese) up to 4 days. Add bread and cheese fresh when reheating.
Leftover Ideas
Nutrition values are estimates calculated per serving and may vary based on brand, preparation method, and serving size. Not a substitute for professional dietary or medical advice. Consult a registered dietitian for specific nutritional needs.
Allergen Notice: Recipes may contain or come into contact with major allergens including milk, eggs, fish, shellfish, tree nuts, peanuts, wheat, soy, and sesame. Always verify ingredient labels for allergen information specific to the brands you use.
Drink pairing suggestions are for adults of legal drinking age only. Please drink responsibly.
Food Safety: Follow USDA safe minimum internal temperatures: Poultry 165°F (74°C), Ground meats 165°F (74°C), Beef/pork/lamb steaks 145°F (63°C) with 3-min rest, Fish 145°F (63°C). Use an instant-read thermometer — do not rely on visual cues alone. Refrigerate leftovers within 2 hours.
