Sprinkle brown gravy mix and ranch mix over the top of the chuck roast.
Place onion pieces on top and sides of the chuck roast.
Cover dish with foil.
Place dish in oven and cook for 1 hour and 20 minutes (20 minutes per pound).
Once cooked cover will foil and allow to rest for 20-30 minutes.
Serve and enjoy.
Notes
Roast in oven for 20 minutes per pound. Once cooked remove from the oven and cover loosely with foil, and let rest for 15 to 20 minutes before slicing.