1. Preheat the oven to 325°F.

2. Season the short ribs generously with salt and pepper.

3. Heat the olive oil in a large, oven-safe Dutch oven or heavy-bottomed pot over medium-high heat. Working in batches if necessary, sear the short ribs on all sides until a deep brown crust forms, about 3-4 minutes per side. Transfer the seared ribs to a plate.

4. Reduce the heat to medium and add the onions to the pot. Cook, stirring occasionally, until softened and lightly caramelized, about 5-7 minutes.

5. Add the garlic and cook for an additional minute, until fragrant.

6. Deglaze the pot with the red wine, scraping up any browned bits from the bottom of the pot. Bring to a simmer and cook for 2-3 minutes to allow the alcohol to evaporate.

7. Stir in the beef broth, tomato paste, bay leaves, and thyme. Return the short ribs and any accumulated juices to the pot, making sure the ribs are mostly submerged in the liquid.

8. Cover the pot and transfer it to the preheated oven. Braise the short ribs for 2 hours, or until the meat is very tender and falling off the bone.

9. Remove the pot from the oven and transfer the short ribs to a serving platter. Discard the bay leaves and thyme sprigs.

10. Bring the braising liquid to a simmer over medium heat and cook for 10-15 minutes, or until the sauce has thickened to your desired consistency.

11. Taste the sauce and adjust seasoning with salt and pepper as needed.

12. Pour the sauce over the short ribs and serve immediately, garnished with fresh thyme if desired. Enjoy!