Light Gratinée Lyonnaise (French Onion Soup)

📝 Ingredients

• 5 brown onions (about 750 g)
• 20 g unsalted butter
• 1 tbsp plain wheat flour
• 2 beef stock cubes + 900 ml hot water
• 3 tbsp white wine vinegar (1 for the soup, 2 for poaching the eggs)
• 1 bay leaf + ½ tsp dried thyme
• 6 slices wholemeal bread (about 30 g each)
• 3 eggs
• 90 g grated Emmental
• Salt, black pepper

🍴 Utensils

• Flameproof casserole dish with lid
• Saucepan
• Slotted spoon
• 3 ovenproof bowls
• Baking tray
• Cutting board and knife

📖 Steps

1. Peel the onions, halve them, then slice thinly into 3 mm half-moons. Use a really sharp knife: it crushes fewer of the onion's cells and makes you cry much less.
2. Melt the butter in a large casserole dish over a medium heat, add the onions and a pinch of salt, which draws out their liquid. Stir, cover and leave to sweat for 10 min, stirring now and then, until well softened.
3. Remove the lid and cook for another 25 to 30 min over a medium-low heat, stirring every 3 to 4 min and scraping the bottom, until the onions are meltingly soft and caramel brown. If they stick, add 2 tbsp water and scrape up the browned bits: that's where all the soup's flavour comes from.
4. Sprinkle over the flour and stir for 1 min to cook it. Pour in the hot water with the crumbled stock cubes, 1 tbsp vinegar, the bay leaf and thyme. Bring to the boil, then simmer for 15 min over a low heat, half covered. Season with pepper and taste before adding salt.
5. Meanwhile, preheat the oven grill. Toast the bread slices for 2 to 3 min under the grill or in the toaster, until dry and golden: well-dried bread soaks up the broth without turning to mush.
6. Bring a saucepan of water to a simmer (small bubbles, not a rolling boil) with 2 tbsp vinegar. Poach the eggs one at a time: crack the egg into a cup, create a whirlpool with a spoon and slide the egg in. Cook for 3 min, lift out with a slotted spoon and drain on kitchen paper.
7. Remove the bay leaf. In each ovenproof bowl, place 1 slice of toasted bread with a poached egg on top, then gently pour the piping hot soup down the sides until the bowl is three-quarters full, without breaking the egg.
8. Place the second slice of bread on the soup and cover with Emmental, letting it spill over the edges. Put the bowls on a baking tray and place under the grill for 4 to 6 min, until the cheese is golden and bubbling. Serve immediately: the bowls will be scorching hot.