Season roast liberally with salt, pepper, garlic and onion powders on both sides, rubbing seasonings into the meat. Sprinkle half of the gravy pack on top of the meat and press it into the meat. Place it into a slow cooker, gravy mix side DOWN. Repeat with other half of gravy mix on top. Cover top of the roast with the can of soup, full strength. Add your veggies on top of the soup and lightly season again with salt and pepper. Cook on High for 4 hours or Low for 6 hours. You can also make this with any of the above combinations of both onion and mushroom.