01 - Generously season the short ribs with salt and black pepper on all sides.
02 - Heat a large skillet over medium-high heat and sear the short ribs for 2 to 3 minutes per side until browned. Transfer the ribs to the slow cooker.
03 - Add chopped onion, sliced carrots, celery, and minced garlic to the skillet. Sauté for 3 to 4 minutes until vegetables begin to soften, then transfer to the slow cooker.
04 - Pour beef broth and dry red wine into the slow cooker. Stir in tomato paste and Worcestershire sauce until combined.
05 - Arrange fresh thyme, rosemary, and bay leaves over the mixture in the slow cooker.
06 - Cover the slow cooker and cook on LOW for 8 hours until ribs are exceptionally tender and meat easily separates from the bone.
07 - Discard bay leaves and herb sprigs. Skim excess fat from the surface, if necessary.
08 - For a thicker sauce, mix cornstarch with water and stir into the slow cooker. Cook on HIGH for an additional 10 to 15 minutes until sauce thickens.
09 - Portion the short ribs hot with sauce and vegetables.