Spray crock pot with cooking spray or use a crock pot liner. Place strips of meat in bottom of slow cooker, followed by thinly sliced onions and peppers. Next add the packet of Italian Seasoning, garlic powder, brown sugar, Worcestershire, bouillon cubes, butter and water. Cover and cook on low for 7-8 hours or high 3-4 hours. Spoon mixture onto toasted buns topped with cheese. Enjoy!