Preheat air fryer to 390 degrees F for 5 minutes. Spray inside of basket with olive oil.
Mix together oil, Worcestershire sauce, rosemary, garlic powder, salt and pepper. Brush this on both sides of meat.
Cook for 15 minutes, then pour remaining oil mixture over the top.
Lower temperature to 320 degrees F and cook for 30-40 minutes depending on weight, thickness, and how well done you want it to be.
Internal temperature should be at least 145 F for consumption, needs to be closer to 200 F. to shred. Remove, allow to rest for 10 minutes, then slice and serve.
How to make gravy - if you want to make gravy from the drippings, pour liquid from air fryer basket into a pot on the stove over medium high heat. Whisk 1 tbsp cornstarch with 3 tbsp cool water until smooth and once bubbling whisk this in. Continue to whisk until thickened to your liking and serve on top.