Preheat Air Fryer: Set air fryer to 400 °F (204 degrees C). Allow it to preheat for 3-5 minutes.
Season Beef: To a mixing bowl, add 1 pound ground beef, 1 teaspoon Worcestershire sauce, 1 teaspoon garlic powder, 1 teaspoon pepper, and ½ teaspoon salt. Gently mix ingredients using your hands or a spoon until evenly combined. Avoid overmixing, or beef can become tough.
Add Beef to Air Fryer: Place seasoned beef in air fryer basket, breaking it into a few large chunks so it cooks evenly.
Cook Beef: Air fry beef for 10-14 minutes (for 90/10 beef, start checking right at 10 minutes). Halfway through cooking, pause air fryer and use a wooden spoon or spatula to break beef into smaller pieces. Stir gently to help it cook evenly. If beef seems to be cooking too quickly, reduce cooking time slightly. Cook until no pink remains and the beef reaches 160 degrees F.
Drain Excess Grease: After cooking, carefully remove basket from air fryer. Using a spoon or spatula, transfer beef to a bowl lined with paper towels, or carefully pour off excess grease. Taste and add more salt (up to the remaining ¼ teaspoon), as desired.
Serve or Store: Serve immediately in tacos, pasta dishes, casseroles, or store cooled beef in an airtight container in refrigerator for up to 3 days or freezer for up to 3 months.