How to Make It
Preheat the oven to 450°. Set the roast fat side up on a rack set in a roasting pan. Rub all over with the olive oil and season with salt and pepper. Add the stock and the rosemary and thyme sprigs to the pan. Roast for 30 minutes, until well browned. Reduce the oven temperature to 350° and roast the meat for about 2 1/2 hours longer, until an instant-read thermometer inserted in the center of the roast registers 125° for medium rare. Transfer to a cutting board and let rest for 30 minutes.
In a small bowl, combine all of the ingredients and mix well. Let the butter stand at room temperature.
In a pot, heat the olive oil. Add the shallots, anchovies and garlic and cook over moderate heat, stirring, until the anchovies dissolve, about 2 minutes. In batches, stir in the escarole until wilted, about 5 minutes. Add the heavy cream and bring to a boil. Simmer briskly until the cream is slightly reduced, about 10 minutes. Add the spinach in batches, stirring, until wilted. Cook, stirring occasionally, until the greens are very tender and the cream is reduced and very thick, about 30 minutes longer. Stir in the lemon zest, lemon juice and crushed red pepper and season with salt and black pepper.
Spread the marjoram butter all over the warm roast. Cut the roast off the bone, then thinly slice. Serve with the creamed escarole and spinach.