Heat 2 tablespoons of olive oil in a large skillet over medium-high heat. Season the beef with salt and pepper, then brown it for 4-5 minutes on each side until golden brown. Transfer the beef to the slow cooker.

In the same skillet, add the chopped onion and minced garlic, sauté for 3-4 minutes until the onion is translucent. Transfer the mixture to the slow cooker.

Pour in 2 cups of beef broth and 2 tablespoons of Worcestershire sauce into the skillet, scraping up any browned bits. Pour the mixture over the beef in the slow cooker.

Add 1 teaspoon of dried thyme, 1 teaspoon of dried rosemary, and additional salt and pepper. Toss in 4 cubed potatoes and 2 cups of baby carrots. Stir gently.

Cover the slow cooker lid tightly and set it to low heat. Cook for about 8 hours, or on high for 4 hours, until the beef is fork-tender.

Toast 4 slices of bread until golden and crispy about 10 minutes before serving.

When ready to serve, place portions of beef and vegetables over the toasted bread. Drizzle with gravy and garnish with parsley.