Whisk together the liquid aminos, oil, water, vinegar, garlic powder, herbs, and pepper in a small baking dish. Place the tofu slices in the baking dish and marinate for 30 minutes, turning the slices over after 15 minutes.
Preheat oven to 400ºF. Transfer the tofu slices to a baking sheet that's been lined with parchment paper or sprayed with cooking spray. Rub any remaining marinade onto the tofu and season with a few sprinkles of salt. For softer baked tofu, bake for 30 minutes; for chewier tofu, bake for 40 minutes. Flip the tofu over halfway through cooking time.