Preheat air fryer to the highest broil setting. (400-450 if using an Instant Pot or Ninja Foodi, 400 for other air fryers)

In a bowl, mix ground beef, Worcestershire sauce, and burger rub.

Using a kitchen scale (or by sight), divide ground beef into four equal balls.

Flatten the balls and press firmly to form patty shapes.

Place patties in broiler/air fryer basket (only place as many as you can fit without having them touch too much.)

Set timer for 10 minutes, and broil on high (for IP it is 400 degrees, 450 for Ninja Foodi).

Flip burger using long handled tongs - be careful as air fryer will be HOT.

Set timer for 5 minutes and broil more.

Check burgers internal temp - if 145+, and you're aiming for medium well done, add cheese. If under 140, broil additional 5 minutes.

When five minutes is up, open lid and add cheese slices. Close lid and let continue cooking for 5 minutes in air fryer heat.

When done cooking, remove and let sit for five minutes before serving.

Wrap in lettuce - either as a double-decker burger, or single patty burgers.

Enjoy!