Wrap the 1 (14-ounce) block extra-firm tofu in paper towels and press with a heavy object (or a tofu press) for 15 minutes to remove excess moisture. After pressing, cut the tofu into 1-inch cubes.

In a medium bowl combine 2 tablespoons low-sodium soy sauce or tamari, 2 1/2 teaspoons seasoned rice vinegar, 3/4 teaspoon sesame oil, 1/2 teaspoon garlic powder, and 1/2 teaspoon onion powder. Stir to make a uniform marinade.

Add the tofu cubes to the bowl with the marinade and gently toss or fold until the tofu is evenly coated. Let the tofu marinate for 15 minutes so it absorbs flavor.

After marinating, sprinkle 1 tablespoon cornstarch over the tofu and toss gently until each cube is evenly dusted with cornstarch.

Preheat the air fryer to 400°F. Arrange the tofu cubes in a single layer in the air-fryer basket, leaving space between pieces for air circulation (cook in batches if necessary).

Air-fry the tofu at 400°F for 10–15 minutes, shaking or turning the basket once about halfway through cooking, until the tofu is golden and crispy. Serve immediately.