
Season beef with salt and pepper.
Place a large cast iron pan or Dutch oven on the stove over heat. Once hot, add oil, and sear roast on all sides.
Place the roast in the slow cooker and add the remaining ingredients from the "Slow Cooker Ingredients" list. Stir well to combine.
Cover and cook on Low for 8-9 hours or High for 5 hours. Until the beef is tender.
Mix water and cornstarch in a small bowl until the cornstarch is fully dissolved.
During the last 30 minutes of cooking, add the slurry to the slow cooker to thicken the gravy. Gently stir to combine the ingredients.
Cover and cook for 30 minutes on High. If needed, add more slurry.
Serve the roast with the veggies and topped with the gravy sauce. Garnish with fresh chopped parsley.