Ingredients:
- Bone-In Beef Rib Joint (Prime Rib), 4–5 lbs (1.8 – 2.3 kg)
- Coarse Sea Salt (e.g., Maldon), 4 Tbsp (60 g)
- Beef Tallow or Lard, 1/2 cup (120 ml), for basting
- Bone Marrow (pre-roasted or scooped), 4 Tbsp (60 g)
- Unsalted Butter, softened, 1/2 cup (115 g)
- Fine Sea Salt, 1/2 tsp (2.5 g)
Instructions:
- Bring to Temperature: Remove the beef joint from the refrigerator 1.5 to 2 hours before cooking. This is vital for even roasting.
- Pat and Season: Pat the entire joint completely dry using paper towels. Rub the coarse salt aggressively all over the joint, ensuring the fat cap and sides are well coated (this acts as a dry brine).
- Preheat: Preheat your oven to 450°F (230°C). Place the roasting rack inside a heavy-duty roasting pan.
- Initial Sear: Place the salted beef joint, fat-side up, directly onto the rack. Cook at 450°F (230°C) for exactly 15 minutes to develop a fantastic outer crust.
- Drop the Heat: Without opening the oven door unnecessarily, reduce the oven temperature to 275°F (135°C).
- Baste and Monitor: Melt the beef tallow/lard. Every 30 minutes, open the oven and generously baste the joint. Begin checking the internal temperature after 1 hour at the lower heat. Insert the thermometer probe into the thickest part of the meat, avoiding the bone.
- Remove the Roast: Remove the roast immediately from the oven when it reaches the target temperature (Recommended medium-rare: 125°F / 52°C).
- Prepare Marrow Butter: While the roast rests, gently scoop the soft, pre-roasted bone marrow into a small bowl. Add the softened unsalted butter and fine salt. Combine thoroughly until smooth and homogenous.
- Rest the Roast: Transfer the hot joint to a cutting board. Tent loosely with foil and let it rest for a full 20–30 minutes. Do not skip or shorten this essential step, as it allows the juices to redistribute.
- Carve and Serve: Carve the roast, slicing against the grain. Serve immediately, topping each slice with a generous dollop of the prepared bone marrow butter.