Method

1. Place beef on a rack, set in an aluminum foil-lined rimmed baking sheet. Sprinkle evenly with salt and pepper, pressing gently to adhere. Refrigerate, uncovered, 24 to 48 hours.
2. Remove beef from refrigerator, and let stand at room temperature 1 hour.
3. Set air fryer to 120°C. Roast for 15-18 minutes total (depending on desired doneness). A thermometer should be inserted in . the thickest portion until it registers 51°C for rare, 55°C for medium-rare.
 Turn half way through roasting time (approx. 8 minutes on each side).
4. On the board, prepare the Fresh Herb Board Dressing by piling flat-leaf parsley, oregano, drained capers, garlic and salt and roughly chop to combine. Transfer to a bowl, stir in red wine vinegar and olive oil.
5. In a mixing bowl, combine sour cream, horseradish, black pepper, salt, grated lemon rind and lemon juice and stir until well blended. Serve as a condiment.
6. Remove beef from air fryer, brush all over from top to bottom with melted butter. Turn air-fryer to 200°C and set for 2 minutes, broil on one side then reset air fryer for another 2 minutes and broil bottom side.
7. Let the beef stand and rest for 15 minutes before carving into thinner slices. Plate on a bed of fresh herb dressing and horseradish sauce.