Season beef with salt and pepper. Heat oil in a medium skillet over medium-high heat, then sear roast on each side for 4 to 5 minutes until browned.
Add potatoes, carrots, onion, garlic and thyme to crock of slow cooker.
Place seared beef on the vegetables, pouring Campbell’s soup, broth (or water), and vinegar over everything. Cover and cook on low for 8 to 10 hours or on high for 5 to 6 hours.
When ready to serve, mix cornstarch and water in a small bowl, then stir into liquid in slow cooker. Allow to cook uncovered on high until sauce is thickened into a gravy. Taste and add salt and pepper, if necessary.
Garnish with parsley, if desired.
Notes
Cut the potatoes in half if they are medium sized potatoes, otherwise leave them whole.
Store leftovers in the refrigerator for up to 3 days.
Nutritional information is based on a 3 pound roast.