01 - Generously season beef short ribs with salt and freshly ground black pepper on all sides.
02 - Heat olive oil in a large skillet over medium-high heat. Sear short ribs on each side for 2 to 3 minutes until well browned. Transfer browned short ribs to the slow cooker.
03 - In the same skillet, add chopped onion, carrots, and celery. Cook for 3 to 4 minutes until vegetables soften. Add minced garlic and sauté for 1 minute more.
04 - Stir tomato paste into the sautéed vegetables and cook for 1 minute. Pour in red wine, scraping up any browned bits from the pan bottom.
05 - Transfer vegetables and sauce to the slow cooker. Add beef broth, Worcestershire sauce, thyme, rosemary, and bay leaves.
06 - Cover and cook on low heat for 7 hours, or on high for 4 to 5 hours, until short ribs are fork-tender and easily pull away from the bone.
07 - Remove bay leaves and herb stems before serving. Skim excess fat from the sauce if desired. Serve short ribs with sauce and vegetables over mashed potatoes, polenta, or egg noodles.