Creating French Onion Beef Short Rib Soup can be straightforward if you follow these detailed steps:

1. Prepare the Beef: Season the beef short ribs with salt and black pepper. Let them sit while you prepare the onions.

2. Caramelize the Onions: In a large Dutch oven, heat olive oil over medium heat. Add the onions and sugar, stirring frequently for about 25-30 minutes, until the onions are golden brown and caramelized.

3. Add Garlic: Mix in the minced garlic and cook for an additional minute until fragrant.

4. Brown the Ribs: Push the onions to the side of the pot and add the beef short ribs. Sear them on all sides until browned (about 3-4 minutes per side).

5. Deglaze with Wine: Pour in the white wine if using, scraping the bottom of the pot to release any browned bits. Allow it to simmer for about 3 minutes.

6. Add Broth and Herbs: Pour in the beef broth, thyme, and bay leaves. Bring the mixture to a gentle boil.

7. Slow Cook: Reduce the heat to low, cover, and let it simmer for 3-4 hours. This slow cooking will tenderize the meat and deepen the flavor.

8. Remove Meat: After cooking, remove the beef short ribs from the pot. Let them cool slightly, then shred the meat, discarding any bones or excess fat.

9. Final Touches: Return the shredded beef to the pot, season with salt and pepper to taste, and let it warm through for a few minutes.

10. Prepare the Baguette: While the soup warms, preheat your oven to 400°F (200°C). Place baguette slices on a baking sheet and toast them for 5-7 minutes, or until golden brown.

11. Serve: Ladle the soup into oven-safe bowls, top with toasted baguette slices, and sprinkle generously with shredded Gruyère cheese.

12. Broil for Cheese: Place the bowls under the broiler for 2-3 minutes, or until the cheese is bubbly and golden brown.