How To Make The Best Pot Roast In Your Slow Cooker (with or without vegetables) | This easy slow cooker pot roast is made with simple ingredients: beef roast, ranch seasoning mix, brown gravy mix and a packet of dry Italian salad dressing! Simply throw everything into your crockpot and cook on low for about 5 hours. Add your vegetables (potatoes, carrots, celery, mushrooms, etc.) and then continue cooking for a few more hours. I absolutely love slow cooking! Perfect for busy moms and dads!