Preheat your oven to 400°F (200°C).

In a small bowl, combine the crushed pink peppercorns, crushed coriander seeds, and a pinch of salt. Mix well to create the spice crust.

Pat the beef tenderloin dry with paper towels. Rub the olive oil all over the tenderloin, then generously coat it with the spice mixture, pressing it onto the meat to adhere.

Heat a cast-iron skillet or oven-safe pan over medium-high heat. Once hot, add the tenderloin and sear it on all sides until browned, about 3-4 minutes per side.

Transfer the skillet to the preheated oven and roast the tenderloin for about 15-20 minutes, or until it reaches your desired level of doneness (130°F for medium-rare).

While the tenderloin is roasting, prepare the whipped bone marrow butter. In a mixing bowl, combine the roasted bone marrow and softened butter. Whip together until well blended and creamy. Season with a pinch of salt, if desired.

Once the tenderloin is done, remove it from the oven and let it rest for 10 minutes before slicing.

Serve the sliced tenderloin topped with a dollop of whipped bone marrow butter and garnish with fresh herbs.