In a medium saucepan, bring enough water to cover the tempeh by about two inches to a boil. Add the tempeh, reduce the heat, and simmer for three minutes. Drain the tempeh and pat it dry. Set aside to cool before using your hands to break the tempeh into small crumbles.

Make the marinade: In a small bowl, mix together the apple, soy sauce, maple syrup, toasted sesame oil, gochujang, garlic, and ginger.

Transfer the marinade to a large zip-top bag along with the tempeh crumbles. Seal the bag and massage the crumbles with the marinade until they are evenly coated. Set aside for 15 minutes.

Preheat the oven to 400 degrees Fahrenheit. Line a baking sheet with Gefen Parchment Paper or a silicone mat. Set aside.

Transfer the marinated tempeh crumbles to a medium bowl and mix in the green onion. Heat the oil in a large skillet over medium-high heat. Add the tempeh and cook for three minutes, stirring constantly to make sure all sides of the crumbles brown. Add 1/4 cup water and cook for about five minutes more, or until the tempeh crumbles hold together and all of the water has been absorbed.

Remove from the heat and set aside for about 5 minutes, or until cool enough to handle. Using a 1/4-cup measure for each patty and your hands, shape 6 patties and place them on the prepared baking sheet.

Bake the patties for 15 minutes before flipping them over. Bake for another 10 minutes.

Meanwhile, if desired, combine the coleslaw mix, rice vinegar, soy sauce, and toasted sesame oil in a medium bowl, mixing well. Season with salt and pepper. Set aside for serving.

Once the patties are done cooking, spread some vegan mayonnaise on the buns, if using. Top with the patties and coleslaw (if using).