Wrap a block of extra firm tofu into 2 sheets of paper towel, place on a plate and weigh it down with something heavy like a cast iron pan to drain the water. Let it drain for 30-40 minutes.
In a shallow bowl combine the cornstarch, Chinese 5 spice mix, garlic powder and salt. Cut the pressed tofu into bite-sized cubes and toss in the spice mixture.
Arrange in an air fryer in a single layer, then spray with a cooking spray, toss and spray again to ensure the tofu cubes are evenly coated. Air fry at 200C/400F for 10 minutes until crispy on the outside and soft on the inside. Open your air fryer and toss once again half way through the cooking.
While the tofu is in the air fryer, prepare the topping. Slice the red chilli and garlic, cut the ginger into thin matchsticks. Heat the oil in a small frying pan or a sauce pan, then fry the aromatic mix until slightly crispy but not burned. Watch carefully. Once see the red chilli starting to lose moisture and curl, take off the heat. Remove the garlic, chilli and ginger from oil with a slotted spoon, shake off the excess oil and place on paper towel lined plate to soak up the rest of the oil. (Reserve the flavoured oil for making stir fries.)
Top the air fryer crispy tofu with the mixture of chilli, garlic and ginger. Then sprinkle with sliced green onions and sesame seeds.
Notes
To cook in an oven, use a slightly higher temperature - 220C/425F - and cook for 12 minutes.