French Onion Soup with Braised Short Ribs

Ingredients:

• 900 g of beef short ribs on the bone
• 2 tbsp. flour
• 2 tbsp. l. rapeseed oil
• 1 carrot, chopped
• 1 medium onion, chopped
• 1 leek, chopped
• 4 sprigs of thyme + 1 tbsp. thyme leaves
• 1 bay leaf
• 1 head of garlic, cut crosswise
• 1 tbsp tomato paste
• 1 cup dry red wine
• 6 cups lightly salted beef broth
• 110 g butter
• 6 Spanish onions, thinly sliced
• 3/4 tbsp. dry sherry
• 1 tbsp sherry vinegar
• 12 slices sourdough bread, toasted
• 12 slices high-quality Gruyere cheese (about 180 g)
• Freshly chopped chives, for serving

Preparation:

1. Toss the ribs with flour and season with salt and pepper. Heat the canola oil in a large cast-iron skillet over medium heat until shimmering. Add the ribs and sear on all sides until golden brown, about 8 minutes. Transfer to a plate.
2. Preheat oven to 160°C.
3. Braise the ribsAdd the carrots, chopped onion, and leek to the pot and cook, stirring, until lightly browned, about 4 minutes. Return the ribs to the pot and add the thyme sprigs, bay leaf, garlic, and tomato paste.
   
   Add the wine and bring to a boil, then simmer until reduced by half, about 5 minutes. Pour in the stock and bring back to a boil. Cover, place in the oven, and simmer until the meat falls off the bone easily, 2 to 3 hours.
4. Meanwhile, caramelize the onions.Melt the butter in a large saucepan over medium heat. Add the chopped onion, season with salt and pepper, and reduce the heat to low. Cook, stirring frequently, until deep golden brown, about 2 hours and 30 minutes (splash a little more water and scrape up any browned bits from the bottom of the pan if necessary).
5. When the ribs are done, remove them from the broth with a slotted spoon, transfer them to a plate, and let cool slightly. Strain the broth to remove any solids. Shred the meat, discarding the bones, and mix with 1 cup of broth. Set the remaining broth aside.
6. Add thyme leaves and sherry to the caramelized onions. Cook until reduced by half, about 3 minutes; add the reserved rib stock and simmer for another 30 minutes. Season with salt and pepper. Skim the fat from the surface of the soup. Stir in the vinegar.
7. Preheat oven to 220°C (425°F). Ladle the soup into 6 ovenproof bowls; spoon about 1/3 cup shredded meat into the center of each serving of soup, then top with 2 slices of toast, trimming the edges if necessary. Top with 2 slices of cheese, letting them hang over the sides of the bowls.
   
   Place in the oven and bake until golden brown, about 10 minutes. Sprinkle with chives.