Preheat your oven to 300°F (150°C). Gather an oven-safe pot or Dutch oven.

In the pot, add 1 tablespoon of olive oil and 1 tablespoon of unsalted butter over medium heat. Sear the 4 beef short ribs for 3-4 minutes on each side until browned.

Remove the ribs, then add 4 large thinly sliced onions, sprinkle with 1 teaspoon of sugar, 1 teaspoon of salt, and ½ teaspoon of black pepper. Cook for 30-40 minutes until caramelized.

Add 4 cloves of minced garlic and sauté for another 1-2 minutes. Pour in 1 cup of dry white wine to deglaze the pot and simmer for 5 minutes.

Add 6 cups of beef broth, 1 tablespoon of Worcestershire sauce, 1 teaspoon of dried thyme, 1 bay leaf, and return the seared ribs to the pot. Bring to a gentle boil.

Cover the pot and transfer it to the oven. Slow cook for 2 to 2.5 hours until the beef is tender.

Remove the ribs, shred the meat, and return it to the soup. Stir well to combine.

Preheat the broiler. Place a slice of crusty French bread on top of the soup in each bowl and sprinkle 2 cups of grated Gruyère cheese over the bread.

Broil the bowls for 2-4 minutes until the cheese is bubbly and golden brown.

Garnish each bowl with freshly chopped parsley and serve hot.