Cut the tempeh into small cubes, put them into an airtight container and add the teriyaki sauce.
Close the airtight container, shake well and put it in the fridge, allowing the tempeh to marinate for at least 1 hour, up to 12 hours.
Preheat the oven to 375°F/190°C and line a baking sheet with parchment paper.
Transfer the tempeh cubes onto the baking sheet and bake for about 15 minutes or until the tempeh is browned and crispy.
Lay out 4 large lettuce leaves, add a quarter or the tempeh to each leaf, and top it with the minced red onion and julienned carrots.
Serve with the optional toppings and enjoy!
Store the tempeh in an airtight container in the fridge, and consume within 2 days. Alternatively, store it in the freezer for a maximum of 60 days and thaw at room temperature. The tempeh can be served cold or reheated in a toaster oven or a non-stick frying pan.