Rump Steak with Roasted Bone Marrow and Parmesan Fries

Roasted bone marrow is butter from the beef itself, and scooping it over a slice of hot steak is one of the richest bites in meat cookery. Canoe-cut bones, split lengthwise, roast faster and more evenly than cross-cut rounds. Rump steak holds up to that richness with a firmer chew and plenty of beefy flavor. Soak the marrow bones in salted water overnight to draw out blood, which keeps the marrow pale. Bake the fries from frozen or double-fry fresh ones; the parmesan goes on while they are hot.