To make the marinade, combine the soy sauce, apple cider vinegar, pure maple syrup, cumin and liquid smoke in a medium bowl. Whisk well to combine.
Place the tempeh strips in a 13 x 9 dish or other large, shallow container, and cover with the marinade. Make sure they are all coated well, and allow to marinate in the refrigerator for at least an hour or overnight.
To Bake: Preheat the oven to 350 degrees F and line a large baking sheet with parchment paper. Place the marinated tempeh strips onto the baking pan. Bake for 15 minutes. Flip and bake for 15 minutes more. Remove and serve.
To Pan Fry: Warm a few tablespoons of oil (olive, canola or avocado oil) in a large pan over medium heat. Add the tempeh in a single layer to the pan, and fry on each side for 3-4 minutes, until golden brown and crispy. For even more flavor, add a few tablespoons of the leftover marinade at the end and stir until coated. Remove, and continue frying until all the tempeh is cooked.
Keep leftover tempeh bacon in a glass or plastic container in the refrigerator for 3-4 days. To reheat, either microwave or put in the oven on a pan for 10-15 minutes, until warmed and crispy. Or eat it cold, as I often do.
Gluten Free: Make sure to use gluten free tempeh, which I believe you can usually find at Whole Foods. Also use tamari instead of soy sauce.
Bake or fry? This is going to taste better pan fried, but it's also perfectly delicious baked! I do both regularly.