Prepare the Marinade
In a large bowl, whisk together the tamari (or soy sauce), maple syrup, cooking oil (if using), sriracha, apple cider vinegar, liquid smoke, garlic powder, sea salt, smoked paprika, and black pepper. This smoky-sweet glaze will give the tempeh its signature flavor.
Cut the Tempeh
Slice the tempeh into cubes, either 24 smaller pieces or 36 depending on how small you prefer the pieces. Smaller pieces provide more surface area for the marinade to soak in, creating a tastier dish.
Marinate the Tempeh
Toss the tempeh cubes in the marinade until they are well coated. Set aside for at least 30 minutes. During this time, it’s a good idea to stir the tempeh once or twice to make sure every piece is coated in the marinade.
Preheat the Air Fryer
While the tempeh marinates, preheat your air fryer to 350°F (175°C). This ensures that the tempeh cooks evenly and crisps up perfectly.
Cook the Tempeh
After the tempeh has marinated, place it in the air fryer basket in a single layer. Add about ¾ to 1 cup of water to the bottom of the air fryer basket to help create steam. This keeps the tempeh moist while it cooks and helps reduce any bitterness. Cook the tempeh for about 10 minutes, checking it halfway through. The tempeh should be golden and slightly crispy around the edges when done.
Serve
Once the tempeh is cooked, remove it from the air fryer and serve immediately. Enjoy it on salads, in grain bowls, or simply as a high-protein snack.