There’s something deeply comforting about a soup that takes its time. French onion soup isn’t about shortcuts or flash — it’s about patience, quiet simmering, and letting simple ingredients turn rich and complex. Slowly caramelized onions form the heart of the broth, transforming into something deeply savory and slightly sweet. Finished with toasted bread and a blanket of melted cheese, it’s a bowl meant to be lingered over.

The soup eats rich but balanced. The broth is dark and fragrant, the onions soft and jammy, and the cheese stretches just enough as you break through the top. It’s warm, indulgent, and grounding — the kind of meal that feels especially right on a cold evening.

The long simmer matters

The first thing you notice is the depth — not heavy, not sharp, just layered. The onions are fully softened, their sweetness rounded and woven into the broth rather than sitting on top of it. The soup eats smooth and rich, with the toasted bread holding its shape just long enough before giving way, and the cheese stretching gently as you pull the spoon through. It’s the kind of bowl that feels complete, steady, and quietly indulgent — the result of letting time do what it does best.

Ingredients

• 3 lb yellow onions, thinly sliced
• 3 tbsp butter
• 1 tbsp olive oil
• 1 tsp salt
• 1 tsp sugar (optional, helps browning)
• 2 cloves garlic, minced
• 2 tbsp all-purpose flour
• ½ cup dry white wine (optional)
• 8 cups beef broth (or beef stock)
• 1 bay leaf
• 2–3 sprigs fresh thyme (or ½ tsp dried thyme)
• Freshly ground black pepper

For serving

• Baguette slices, toasted
• Gruyère cheese, grated (Swiss works as a substitute)

Instructions

1. Slowly caramelize the onions.
   In a large pot or Dutch oven over medium heat, melt the butter with the olive oil. Add the onions and salt, stirring to coat. Cook uncovered for 35–45 minutes, stirring often, until the onions are deep golden brown and very soft. Sprinkle in the sugar during the last 10 minutes if using.
2. Build the base flavor.
   Stir in the garlic and cook for 30 seconds until fragrant. Sprinkle the flour over the onions and cook for 1–2 minutes, stirring constantly, until the flour is absorbed.
3. Deglaze the pot.
   If using wine, pour it in and scrape up any browned bits from the bottom of the pot. Let it simmer for 2–3 minutes until slightly reduced. If skipping the wine, use a splash of broth instead and proceed to the next step.
4. Simmer the soup.
   Add the beef broth, bay leaf, and thyme. Bring to a gentle simmer, then lower the heat and cook uncovered for 20–30 minutes. Season with black pepper and adjust salt to taste.
5. Prepare the topping.
   Preheat the broiler. Ladle the soup into oven-safe bowls, place toasted baguette slices on top, and cover generously with grated cheese.
6. Broil until bubbly.
   Broil for 2–4 minutes, watching closely, until the cheese is melted and lightly browned. Serve hot.

Why a Dutch Oven?

A Dutch oven is one of the best tools for making soup. Its heavy cast-iron walls hold heat evenly, so your soup simmers gently without scorching. The thick lid keeps moisture locked in, helping flavors deepen as everything cooks together. It’s also roomy enough for generous batches, perfect for family meals or storing leftovers.

Another bonus is versatility: you can sauté onions, brown meat, and simmer broth all in the same pot, so fewer dishes pile up in the sink. Whether on the stovetop or finished in the oven, a Dutch oven makes the process simple and reliable—just the way soup should feel.

Affiliate note: I use this Dutch oven (affordable and dependable), and it has served me well for everyday cooking. If you like cooking in bigger batches, the larger 7-quart version is great for soups and stews that feed a crowd. There are also higher-end options like this one or this one, which many cooks love for brand reputation and long-term reliability.

Storage

• Store leftover soup (without bread or cheese) in the refrigerator for up to 4 days.
• Reheat on the stove over low heat, then add bread and cheese just before serving.

Note

• This soup improves with time. The flavor deepens if made a day ahead and reheated gently.
• Gruyère is traditional, but a mix of Gruyère and Swiss gives a nice balance of melt and flavor.
• If skipping wine, add a splash of extra broth and a small squeeze of lemon at the end for brightness.

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Thank you for being here as I start this journey. I can’t wait to share more recipes, tips, and stories with you — one crumb at a time.

Stay tuned,
~ Clever Crumbs