When you take the beef out of the fridge, use a paper trowel to dry it and then set it aside. If you are taking a large piece of beef then cut it into two pieces because medium size cutlets are more prone to be evenly roasted compared to a large piece of beef. Leave the beef out of the fridge in the kitchen for 30 minutes and prepare other things.
Turn the air fryer on and then leave it for 2 to 5 minutes until you find that it is ready to accept the ingredients. The purpose of preheating is to make sure that beef is evenly roasted. Leave the air fryer on at 400 degrees F and move to the other ingredients.
It is time to coat the seasoning on the beef so take a bowl and mix all the seasonings including salt, black pepper and mustard powder as well as other seasonings. Use an oil brush to coat beef pieces with oil and then press seasonings all over the beef until you find that seasonings stick to the beef.
Place the pieces of beef into the basket and then cook for 10 minutes at 400 degrees F. Roasting beef takes more time in the pan compared to an air fryer but still, you need to cook it for at least 40 to 45 minutes if you have an air fryer. After 10 minutes, flip the beef with the help of tongs and reduce the temperature to 350 degrees F then cook for a further 30 minutes.
After 40 minutes use a thermometer to check the internal temperature of the beef. Usually, 120 degrees F is considered rare, 130 degrees F is known as medium rare, 140 degrees F is called medium, 150 degrees F is medium well and 160 degrees F is well done. When the beef reaches your desired temperature, take the basket out and transfer the beef to a platter.
Wrap an aluminum foil around the piece of beef and then leave it for 20 to 30 minutes to make sure all the seasonings are infused. In this way, the roasted beef will be more juicy, soft and scrumptious. Use a knife and cutting board to cut the beef into pieces and then serve it in a dish.