How Chefs Make French Onion Soup (It's Not About the Onions)

Ingredients

• 2 pounds Beef Bones with Marrow (mixed beef bones with marrow, optional but adds depth)
• 1 pound Beef Trim (aged ribeye trim or cheap stewing steak, roasted for stock)
• 4 cups Store-Bought Beef Stock (low‑sodium, used as base for the homemade stock)
• 2 cups Store-Bought Chicken Stock (light flavor to balance the beef richness)
• 2 pieces Carrots (roughly chopped, adds sweetness to stock)
• 2 stalks Celery Stalks (roughly chopped, adds aromatics)
• 1 piece Onion (for stock) (medium, roughly chopped)
• 2 cloves Garlic (minced)
• 2 sprigs Fresh Thyme (plus extra for garnish)
• 1 sprig Fresh Rosemary (optional, adds depth)
• 1 cup Dry Red Wine (helps deglaze and adds sweetness)
• 4 pieces Spanish or Roscoff Onions (thinly sliced, sweet flavor for caramelization)
• 4 tablespoons Unsalted Butter (for sautéing onions and making roux)
• 2 tablespoons All-Purpose Flour (for the burmanet (roux))
• 1 loaf French Baguette (day‑old, sliced 1‑inch thick for topping)
• 1 cup Gruyère Cheese (shredded, for broiling)
• 2 tablespoons Fresh Chives (chopped, garnish)
• to taste Salt (for seasoning onions and final soup)
• to taste Black Pepper (freshly ground)

Instructions

1. Roast Bones and Beef Trim

   Preheat the oven to 180°C (350°F). Place the beef bones with marrow and the beef trim on a roasting pan, rub lightly with salt, and roast for about 35 minutes until golden‑brown but not burnt.

   Time: PT35M

   Temperature: 180°C

2. Prepare Aromatics for Stock

   While the bones roast, roughly chop carrots, celery, and a medium onion. Mince garlic. Set aside.

   Time: PT10M

3. Deglaze with Wine

   Remove the roasted bones and trim from the oven. Transfer to the Dutch oven, add the chopped vegetables, garlic, thyme, and rosemary. Pour in 1 cup of dry red wine, scraping up any browned bits. Reduce the wine by half over medium heat.

   Time: PT10M

4. Simmer the Stock

   Add the roasted bones, beef trim, 4 cups beef stock, 2 cups chicken stock, and enough water to cover (about 2‑3 quarts). Bring to a gentle simmer, then reduce heat to low and cook uncovered for 1 hour 30 minutes, skimming the surface every 20 minutes to remove foam and excess fat.

   Time: PT90M

5. Strain and Finish Stock

   After simmering, remove the bones and vegetables. Strain the liquid through a fine mesh sieve into a clean pot. Discard solids. Add additional 2 cups of light chicken stock if the broth is too intense. Keep warm on low heat.

   Time: PT10M

6. Caramelize Onions

   In a large heavy‑bottom pan, melt 4 tbsp butter over low heat. Add the sliced onions, sprinkle with a pinch of salt, cover, and cook for 25 minutes, stirring occasionally. Uncover and continue cooking, stirring frequently, for another 5‑7 minutes until the onions are deep golden and sweet but not burnt.

   Time: PT30M

7. Make the Burmanet (Roux)

   In a separate small saucepan, melt 2 tbsp butter, whisk in 2 tbsp flour, and cook over medium‑low heat, stirring constantly, until the mixture turns a light golden color (about 3‑4 minutes). Do not let it brown too dark.

   Time: PT5M

8. Combine Roux and Stock

   Whisk the roux into the warm stock a little at a time, ensuring no lumps form. Bring the soup to a gentle boil for 5 minutes to cook out the raw flour taste, then reduce to a low simmer.

   Time: PT10M

9. Season and Finish Soup

   Taste the soup and adjust with salt and freshly ground black pepper. Add the caramelized onions, stirring to distribute evenly. Keep the soup warm.

   Time: PT5M

10. Prepare Bread and Cheese Topping

    Preheat the broiler. Slice the baguette into 1‑inch thick rounds, place on a baking sheet, and toast lightly for 2 minutes. Top each slice with a generous amount of shredded Gruyère.

    Time: PT5M

11. Broil and Serve

    Ladle hot soup into oven‑safe bowls, float a cheese‑topped baguette slice on top of each, and place under the broiler until the cheese bubbles and turns golden (about 2‑3 minutes). Garnish with chopped chives and a sprig of thyme.

    Time: PT5M

Nutrition Facts

Calories

250

Protein

12g

Carbohydrates

20g

Fat

12g

Fiber

2g