Season the short ribs generously with salt and black pepper on all sides.

Heat the olive oil in a large skillet over medium-high heat. Add the short ribs and sear them on all sides until browned, about 3-4 minutes per side. Transfer the seared short ribs to the slow cooker.

In the same skillet, add the chopped onion, carrots, celery, and minced garlic. Cook, stirring occasionally, until the vegetables are softened, about 5 minutes.

Transfer the cooked vegetables to the slow cooker with the short ribs.

In a mixing bowl, whisk together the beef broth, red wine, tomato paste, bay leaves, dried thyme, dried rosemary, and Worcestershire sauce until well combined. Pour the mixture over the short ribs and vegetables in the slow cooker.

Cover the slow cooker and cook on low heat for 8-10 hours, or on high heat for 4-6 hours, until the short ribs are tender and falling off the bone.

Once the short ribs are done cooking, carefully remove them from the slow cooker and transfer them to a serving platter. Skim off any excess fat from the cooking liquid in the slow cooker.

Optional: For a thicker sauce, you can strain the cooking liquid into a saucepan and simmer it over medium heat until it reduces and thickens slightly.

Serve the braised short ribs with the reduced cooking liquid spooned over the top. Garnish with chopped fresh parsley, if desired.

Enjoy your delicious Slow Cooker Red Wine Braised Short Ribs with your favorite sides, such as mashed potatoes, roasted vegetables, or creamy polenta.