Soupe à l'Oignon

About This Recipe

French Onion Soup is the soul of French bistro cooking — slowly caramelized onions simmered in rich beef broth, topped with toasted bread and bubbling, golden Gruyère cheese. The technique is simple but the result is profound: sweet caramelized onions, deeply savory broth, and the irresistible cheese-pulled crust. It's traditionally eaten in the early hours by Parisian market workers.

Ingredients

Serves 4

• 1.5 kgyellow onions, thinly sliced
• 4 tbspunsalted butter
• 2 tbspolive oil
• 1 tspsugar
• 1 tspsalt
• 3 clovesgarlic, minced
• 1/2 cupdry white wine
• 1/4 cupbrandy or cognac
• 1.5 Lrich beef stock
• 2 sprigsfresh thyme
• 1bay leaf
• 2 tspbalsamic vinegar
• 8 slicesbaguette, 2cm thick
• 200 gGruyère cheese, grated
• 50 gParmesan, grated

Instructions

1. 1

   Caramelize onions

   Melt butter and oil in large heavy pot over medium-low heat. Add onions, sugar, and salt. Cook stirring occasionally for 60 minutes until deeply caramelized — golden brown. This is the most important step. Don't rush.

2. 2

   Add garlic

   Add garlic, cook 1 minute.

3. 3

   Deglaze

   Pour in wine and brandy, scrape any browned bits. Reduce until almost evaporated, 5 minutes.

4. 4

   Add stock

   Add beef stock, thyme, and bay leaf. Bring to simmer. Cook 30 minutes uncovered to develop flavor.

5. 5

   Finish

   Stir in balsamic vinegar. Adjust salt and pepper. Discard bay leaf.

6. 6

   Toast bread

   Toast baguette slices until golden. Rub with garlic clove if desired.

7. 7

   Assemble

   Ladle soup into oven-safe bowls. Float 2 toast slices on each. Top generously with Gruyère and Parmesan.

8. 8

   Broil

   Place bowls on baking sheet. Broil 3-5 minutes until cheese is bubbly, golden, and slightly browned around edges.

9. 9

   Serve

   Serve immediately while cheese is hot and stretchy. Warn diners — bowls are very hot.

Variations

• •

  Use red wine for darker, deeper soup.

• •

  Add a splash of port for sweetness.

Storage

Refrigerate soup base 5 days. Toast and broil cheese fresh per serving.

Frequently Asked Questions