Begin by patting the bone-in beef short ribs dry with paper towels. Generously season each rib with salt and freshly ground black pepper.

Heat a tablespoon of olive oil in a large skillet over medium-high heat. Once hot, add the seasoned short ribs, searing them for 2-3 minutes on each side.

Transfer the seared ribs into the slow cooker, arranging them snugly at the bottom.

In the same skillet, add chopped onions and carrots, sautéing for 3-4 minutes until the onions become translucent. Then add minced garlic and sauté for an additional 30 seconds.

Transfer this aromatic mixture into the slow cooker, spreading it over the short ribs for enhanced flavor.

In a mixing bowl, whisk together beef broth, red wine, tomato paste, Worcestershire sauce, soy sauce, and brown sugar until well combined.

Pour the sauce evenly over the short ribs and vegetables in the slow cooker.

Place fresh thyme, rosemary, and a bay leaf into the slow cooker, tucking them among the ingredients.

Cover the slow cooker with its lid and set it to cook on low for 7-8 hours or on high for 4-5 hours.

If you desire a thicker sauce, strain the cooking liquid into a saucepan and bring it to a simmer. Whisk in cornstarch slurry until thickened.