Soupe à l'oignon gratinée

A classic French bistro soup: slowly caramelized onions in a rich broth, topped with toasted baguette slices and melted Gruyère and baked until gratinéed. Warming and filling, and a real treat as a starter too.

By yumbelo · 4 servings · 75 minutes

Ingredients

• 1000 g Yellow onions
• 50 g Butter
• 1 tbsp Cooking oil
• 1 tsp Sugar
• 15 g Wheat flour
• 1500 ml Vegetable broth
• 1 pc Thyme sprig
• 1 pc Bay leaf
• 160 g Baguette
• 120 g Gruyère, grated
• Salt
• Black pepper, freshly ground

Method

1. Peel the onions, halve them and slice them into thin rings.
2. Heat the butter and cooking oil in a large pot over medium heat. Add the onions with a pinch of salt and let them caramelize to a golden brown over about 30 minutes, stirring occasionally, reducing the heat slightly if needed.
3. Sprinkle in the sugar and fry for another minute while stirring.
4. Dust the flour over the onions, stir in well and let it sweat briefly.
5. Gradually pour in the vegetable broth, stirring well so no lumps form. Add the thyme and bay leaf and let the soup simmer gently, uncovered, for about 20 minutes.
6. Remove the thyme and bay leaf and season with salt and pepper.
7. Preheat the oven to 200 °C top and bottom heat. Cut the baguette into 8 thin slices and toast them in the oven for about 5 minutes until golden brown.
8. Ladle the soup into four ovenproof bowls. Place two baguette slices on each and sprinkle generously with Gruyère.
9. Place the bowls on a baking sheet in the oven and bake for about 8 to 10 minutes, until the cheese is golden brown and bubbly. Serve hot.