Step 1

Preheat air fryer to 390°F (200°C).

Step 2

Mix sea salt, rosemary and oil on a plate.

Step 3

Pat the beef roast dry with paper towels. Place beef roast on plate and turn so that the oil-herb mix coats the outside of the beef.

Step 4

If using, peel onion and cut it in half, place onion halves in the air fryer basket.

Step 5

Place beef roast in the air fryer basket.

Step 6

Set to air fry beef for 15 minutes.

Step 7

When the time is up, change the temperature to 360°F (180°C). Some air fryers require you to turn food during cooking, so check your manual and turn the beef roast over if required (my Philips Viva airfryer doesn't need food to be turned).

Step 8

Set the beef to cook for an additional 30 minutes. This should give you medium-rare beef. Though is best to monitor the temperature with a meat thermometer to ensure that it is cooked to your liking. Cook for additional 5 minute intervals if you prefer it more well done.

Step 9

Remove roast beef from air fryer, cover with kitchen foil and leave to rest for at least ten minutes before serving. This allows the meat to finish cooking and the juices to reabsorb into the meat.

Step 10

Carve the roast beef thinly against the grain and serve with roasted or steamed vegetables, wholegrain mustard, and gravy.