French Onion Soup Recipe
A long, patient caramelization over low heat, not a quick browning, is what develops the deep sweetness that gives this soup its color and flavor, there's no shortcut that replicates 45 minutes of slowly cooked onions.
- Prep
- 20 min
- Cook
- 75 min
- Total
- 95 min
- Servings
- 4
Ingredients
- 3 lb yellow onions, thinly sliced
- 4 tbsp unsalted butter
- 1 tbsp olive oil
- 1 tsp salt
- 1/2 tsp sugar
- 1/2 cup dry sherry or white wine
- 6 cups beef stock
- 2 sprigs fresh thyme
- 1 leaf bay leaf
- 8 slices baguette, sliced into rounds
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Instructions
- 1Melt the butter with the olive oil in a large heavy pot over medium heat.
- 2Add the onions, salt, and sugar, and cook, stirring occasionally, for 45-50 minutes, until deeply golden brown and jammy.
- 3If the onions start to stick or scorch, reduce the heat and add a splash of water, scraping up the browned bits.
- 4Add the sherry and cook 2 minutes, scraping up any remaining browned bits from the bottom of the pot.
- 5Add the beef stock, thyme, and bay leaf, bring to a simmer, and cook uncovered for 20 minutes.
- 6Discard the thyme stems and bay leaf, and season the soup to taste with salt and pepper.
- 7Toast the baguette slices until golden.
- 8Ladle the soup into oven-safe crocks, top each with two toasted baguette slices, and cover generously with grated gruyere.
- 9Broil until the cheese is melted and bubbling with golden spots, 2-4 minutes, watching closely.
Tips & variations
- Vidalia or other sweet onions caramelize a little faster and add extra sweetness, though yellow onions give the most classic depth.
- No sherry on hand, a dry white wine or even a splash of brandy works as a substitute.
- Swap in vegetable stock and skip the sherry's meat pairing entirely for a vegetarian version, the caramelized onions still carry most of the flavor.
- Comte or a mix of gruyere and mozzarella both make a good substitute if gruyere isn't available.
Storage & reheating
Refrigerate the soup base (without bread or cheese) up to 4 days, or freeze up to 3 months. Reheat on the stovetop, then assemble and broil the bread and cheese fresh just before serving.
Nutrition
A rich, savory soup, the melted cheese and buttered onions make it more indulgent than a typical broth-based soup.
Tips from the Tulo kitchen
- Use a wide, heavy pot rather than a narrow one, more surface area means the onions caramelize faster and more evenly.
- Resist stirring constantly during the caramelization, let the onions sit for a few minutes between stirs so they actually get a chance to brown.
FAQ
Why is my onion soup bitter?
Onions that scorch rather than caramelize turn bitter, if they're browning too fast, lower the heat and add a splash of water to slow things down and keep them from burning.
Can I use chicken stock instead of beef stock?
Beef stock gives the traditional deep, savory flavor, but chicken stock works in a pinch, the soup will just taste lighter and less robust.
What if I don't have oven-safe bowls?
Broil the cheese-topped bread separately on a baking sheet, then float each toast on top of a bowl of hot soup instead.
