Prepare the Tofu: Mix salt in water and stir until dissolved. Soak the cubed tofu in salted water for 10 minutes.
Air Fry the Tofu: Preheat your air fryer to 400°F for 3 minutes. Lightly grease the air fryer basket with oil to prevent sticking. Line the air fryer with the tofu in a single layer without over crowding. Spray oil on top of tofu. Cook at 400°F for 10 minutes. Flip. Spray oil again then air fry for another 10 minutes until golden and crispy.
Stir fry: Add a little oil to your pan over medium heat, stir fry the garlic for 30 seconds. Add in red pepper and green onions and stir fry for another 30 seconds. Add in air fried tofu and season with garlic salt and a few dashes of white pepper. Mix altogether.
Serve: Turn off heat and plate. Be sure to get all the little bits to the plate. Optional, garnish with freshly chopped spring onions or cilantro for a burst of freshness.