Soupe à l'Oignon
A classic French caramelized onion soup with toasted bread and melted Gruyère. Rich, warming, and surprisingly simple—the slow cook transforms humble onions into liquid gold.
- Total time
- 50 min
- Servings
- 4
- Calories
- 380
- Protein
- 14g

Ingredients
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Open the appInstructions
Step 1
Melt butter with oil in a large pot over medium heat, about 1 minute.
Step 2
Add sliced onions and stir to coat. Cook uncovered for 30–35 minutes, stirring occasionally.
Step 3
Onions should be deep golden brown and very soft. Scrape any browned bits from the bottom.
Step 4
Pour wine into the pot and stir, scraping up caramelized bits. Cook 2 minutes.
Step 5
Add broth and bring to a gentle simmer. Cook for 10 minutes uncovered.
Step 6
Taste and season generously with salt and pepper.
Step 7
Preheat broiler to high. Arrange baguette slices on a baking sheet in a single layer.
Step 8
Broil bread 2–3 minutes per side until golden brown and crispy.
Step 9
Ladle soup into broiler-safe bowls or crocks. Top each with a piece of toasted bread.
Step 10
Cover bread generously with Gruyère. Broil 3–4 minutes until cheese bubbles and browns.
Step 11
Cool 1–2 minutes. Serve immediately.
Tools you’ll need
- large heavy-bottomed pot (5-quart minimum)
- baking sheet
- broiler-safe bowls or crocks
- wooden spoon
- ladle
- box grater
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