Prep the tofu. Drain the block and wrap it in a clean kitchen towel.
Set a plate and a heavy pan on top. Press for 15–20 minutes to remove excess water. If you’re short on time, give it a firm pat-dry and move on.
Cut into cubes. Slice the tofu into 3/4- to 1-inch cubes.
Keep them similar in size for even cooking.
Mix the marinade. In a large bowl, whisk soy sauce, sesame oil, rice vinegar, maple syrup, garlic, onion powder, and black pepper.
Toss to coat. Add the tofu cubes to the bowl and gently toss. Let them sit for 10 minutes to absorb flavor. Stir once halfway so every side gets seasoned.
Add cornstarch. Sprinkle cornstarch over the tofu and toss gently until each piece looks lightly dusted and no dry patches remain.
The coating should cling, not clump.
Preheat the air fryer. Set it to 390–400°F (200°C) for 3–5 minutes. A hot basket jump-starts crisping.
Lightly oil. Spray or brush the basket with a thin layer of oil. This helps prevent sticking and boosts browning.
Arrange in a single layer. Space the cubes so air can flow around them.
Work in batches if needed. Lightly mist the tops with oil for extra crunch.
Air fry. Cook for 12–15 minutes, shaking the basket or turning the tofu at the 7-minute mark. They’re done when deeply golden with crisp edges.
Season and serve. While hot, toss with a pinch of salt, chili flakes, or sesame seeds.
Serve with a dipping sauce or over rice, greens, or noodles.