- Preheat oven to 180C.
- For the Beef Fillet, trim sinew and excess fat from the beef. Wrap tightly in cling film and holding the two ends of the cling film, roll into a log and secure to keep fillet in a cylinder shape. Set aside in fridge for 30 minutes.
- Remove beef from cling film, season generously with salt. Allow beef to come to room temperature and absorb seasoning for at least 15 minutes.
- Heat an oven safe griddle pan over high heat. When hot, drizzle beef with olive oil then sear in the pan on all sides until browned all over.
- Cook beef in the oven until the internal temperature reaches 48-50C or longer until cooked to your liking. Remove from the oven and allow to rest for at least 15 minutes. Carve into slices to serve.
- For the Chimichurri Sauce, wash herb leaves thoroughly under cold running water. Place into a blender along with remaining ingredients and process to a thick smooth paste. Season with salt and pepper, to taste. Transfer to a small serving bowl.
- Serve sliced Eye Fillet on a large plate with the Chimichurri on the side.