Cut the tempeh block into thin slices, about ¼ inch thick. You can slice them into strips to resemble bacon or cut them into any desired shape.
In a shallow dish, whisk together marinade ingredients.
Place the tempeh slices into the marinade, ensuring each piece is coated evenly. Let it marinate for at least 2 hours to allow the flavors to develop. You can also marinate it overnight in the refrigerator for a more intense flavor.
Preheat the air fryer according to the manufacture instructions.
Once marinated, place the tempeh slices in a single layer in the air fryer basket, making sure they're not overlapping.
Cook the tempeh in the air fryer for 10-15 minutes at 190C/375F degrees, flipping halfway through the cooking time.
Keep an eye on the tempeh as it cooks to prevent burning. You want it to turn crispy and golden brown.
Once the tempeh bacon is cooked to your desired level of crispness, remove it from the air fryer and let it cool for a few minutes before serving.
Enjoy your homemade keto-friendly, vegan tempeh bacon! You can serve it as a side dish, in sandwiches, in a salad, or any way you like.