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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
Soupe à l'Oignon
comfortelegantfrenchvegetariancreamymeltyweeknightcozy

Ingredients

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Instructions

  1. Step 1

    Melt butter with oil in a large pot over medium heat, about 1 minute.

  2. Step 2

    Add sliced onions and stir to coat. Cook uncovered for 30–35 minutes, stirring occasionally.

  3. Step 3

    Onions should be deep golden brown and very soft. Scrape any browned bits from the bottom.

  4. Step 4

    Pour wine into the pot and stir, scraping up caramelized bits. Cook 2 minutes.

  5. Step 5

    Add broth and bring to a gentle simmer. Cook for 10 minutes uncovered.

  6. Step 6

    Taste and season generously with salt and pepper.

  7. Step 7

    Preheat broiler to high. Arrange baguette slices on a baking sheet in a single layer.

  8. Step 8

    Broil bread 2–3 minutes per side until golden brown and crispy.

  9. Step 9

    Ladle soup into broiler-safe bowls or crocks. Top each with a piece of toasted bread.

  10. Step 10

    Cover bread generously with Gruyère. Broil 3–4 minutes until cheese bubbles and browns.

  11. 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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