Set your air fryer to 400°F (200°C) and let it preheat.
Wash the white asparagus thoroughly under cold water to remove any dirt or debris.
Trim off the woody ends, typically about 1-2 inches from the bottom.
Using a vegetable peeler, peel the asparagus starting from just below the tip (1-1.5 inches from the tip going down) to the bottom to remove the tough outer layer.
Cut a piece of parchment paper large enough to wrap the asparagus spears. Dampen the parchment paper with water.
Place the asparagus in the center of the parchment paper. Add the butter, lemon pepper, a pinch of sugar, salt, and pepper to taste, then combine.
Use a kitchen thread to wrap the parchment paper securely.
Place the wrapped asparagus in the preheated air fryer basket and air fry for 30-50 minutes, depending on the thickness of the spears.
Check for tenderness by carefully bending a spear or piercing the thickest part with a fork or knife.
Once done, carefully remove the parchment paper from the air fryer. Transfer the asparagus to a plate.
Optionally, drizzle with a bit more melted butter or sprinkle additional lemon pepper (or lemon juice) before serving.