French Onion Soup

Ingredients

• Onions · large, thinly sliced, ~800g4
• Butter3 tbsp
• Olive oil1 tbsp
• Sugar · to help caramelize, optional1 tsp
• Flour · to thicken, optional1 tbsp
• White wine · optional, to deglaze100 ml
• Beef stock (or vegetable)1 L
• Thyme · or a little dried2 sprigs
• Salt & pepper1 to taste
• Cheese toast
• Baguette4 slices
• Gruyère (or Emmental) · grated100 g

Steps

1. Melt the butter and olive oil in a wide pot, add the sliced onions, and caramelize over medium-low heat 25–35 minutes, stirring often, until deep golden brown (a little sugar helps). Going slow is the key.

   ⏲ 30 min

2. Stir in the flour and cook 1 minute, then pour in the wine and scrape up the bottom as it reduces.

   ⏲ 2 min

3. Add the stock and thyme, bring to a boil, then simmer 15–20 minutes. Season with salt and pepper.

   ⏲ 20 min

4. Lightly toast the baguette slices. Preheat the broiler.

   ⏲ 5 min

5. Ladle the soup into oven-safe bowls, top with the baguette, and cover generously with cheese.

   ⏲ 2 min

6. Broil 3–5 minutes until the cheese is melted, golden, and bubbling. Serve hot.

   ⏲ 5 min

Tips & Variations

The basics behind this dish

• Salt: When You Add It Matters More Than How MuchThe same amount of salt either draws water out or seasons all the way through, depending on when it goes in. Osmosis, seasoning in layers, and why salt types are not interchangeable by volume.
• Browning and the Maillard ReactionMeat fails to brown for one of three reasons: it is wet, the pan is cool, or you put too much in at once. Plus how the brown film stuck to the pan becomes your sauce.
• Stocks and Broths: Clarity, Time, and Why You Do Not Salt ThemWhat separates a clear stock from a cloudy one is temperature, not ingredients. Why you start in cold water, how long each ingredient wants, and why salt comes later.