01 - Preheat oven to 325°F. Pat the beef short ribs thoroughly dry with paper towels and season generously on all sides with salt and freshly ground black pepper.
02 - Heat olive oil in a large Dutch oven or heavy ovenproof pot over medium-high heat. Sear the short ribs on all sides until a deep golden-brown crust forms, approximately 3 to 4 minutes per side. Transfer the seared ribs to a plate and set aside.
03 - Add the chopped onion, carrots, and celery to the pot. Sauté until the vegetables are softened and lightly caramelized, about 5 minutes. Add the minced garlic and cook for 1 additional minute until fragrant.
04 - Stir in the tomato paste and cook for 1 minute to caramelize. Pour in the dry red wine, using a wooden spoon to scrape up any browned bits from the bottom of the pot. Bring to a boil and let the wine reduce by half, approximately 10 minutes.
05 - Return the seared short ribs to the pot along with any accumulated juices. Pour in the beef broth and add the thyme sprigs, rosemary sprigs, and bay leaves. The liquid should nearly cover the ribs. Bring to a gentle simmer on the stovetop.
06 - Cover the pot with a tight-fitting lid and transfer to the preheated oven. Braise for 2 hours 30 minutes to 3 hours, checking occasionally, until the meat is fork-tender and falling off the bone.
07 - Carefully remove the ribs and vegetables to a serving platter. Discard the thyme sprigs, rosemary sprigs, and bay leaves. Skim excess fat from the surface of the braising liquid. For a thicker, more concentrated sauce, reduce the liquid on the stovetop over medium-high heat until it reaches the desired consistency.
08 - Serve the braised short ribs hot, spooning the reduced sauce generously over the top. Pair with creamy mashed potatoes, polenta, or crusty bread to soak up the rich braising liquid.