NYT Cooking: An Internet darling of a recipe, a favorite of mom bloggers and Pinterest, Mississippi Roast is traditionally made by placing a chuck roast in a slow cooker and simmering it beneath a stick of butter, a package of ranch dressing mix, another of “au jus” gravy mix and a handful of pepperoncini. And you can certainly cook it that way. The raves are justified. But replacing the packaged mixes is no r
