Heat a drizzle of olive oil in a large skillet over medium-high heat. Season your beef stew meat with salt and pepper, then carefully add it to the hot skillet. Sear the beef cubes for about 2-3 minutes on each side, or until they develop a rich, brown crust. Once seared, transfer the beef into your slow cooker.

In the same skillet, melt 2 tablespoons of unsalted butter over medium heat. Add minced garlic and cook for approximately 1 minute, stirring frequently until the garlic becomes fragrant and lightly golden. Transfer to slow cooker.

Pour in the beef broth and Worcestershire sauce into the skillet, ensuring you scrape up any browned bits stuck to the bottom. Stir in the dried thyme and rosemary, mixing well. Pour this flavorful sauce over the beef in the slow cooker.

Next, add the halved baby potatoes to the slow cooker. Gently toss the potatoes with the beef and sauce. Place the remaining 2 tablespoons of unsalted butter on top of the mixture.

Cover the slow cooker with its lid and set it to cook on low for 6-7 hours or high for 3-4 hours.

Once cooked, check the tenderness of the beef and potatoes. Season with additional salt and pepper, and garnish with chopped parsley if desired before serving warm.