This recipe is on the back of a dry onion soup mix package (Wyler & Company) and was found in a large collection, marked date is 1964 (by The Borden Co.). I’ve typed it below along with a scanned copy.
Baked Pot Roast
Place 4-5 lb. pot roast on heavy aluminum foil in baking pan. Empty contents of this package over meat (RecipeCurio note: this is a 1 1/4 oz. package of Wyler & Co. Dry French Onion Soup Mix). Close foil tightly. Bake in 350° oven for 2 1/2 hours. Open foil and bake 1/2 hour longer. Use juice for gravy. 6 to 8 servings.