Mix ingredients for Marinade in a saucepan. Bring it to boil, simmer it on low-medium heat until it thickens to maple syrup-like consistency and reduces in amount by half. Be careful to avoid overcooking, sauce will thicken more as it cools down. Place to side.
While sauce is simmering, press the water out of tofu and cut it into small cubes. Coat the tofu cubes with 2 tablespoons of marinade gently, making sure the tofu cubes do not break. Let marinate for 30-40 minutes.
Place 1-2 tablespoons of oil in a large pan. Once warm, place marinated tofu into the pan and flip sides of tofu every few minutes, making sure it does not burn.The moisture from the tofu will evaporate and tofu will start to brown. Put the cooked tofu aside once complete.
Heat remaining 1-2 tablespoons of oil in a pan. Add minced garlic and grated ginger. Cook for a minute until soft, being careful not to burn.
Add thinly sliced onion and cook until translucent, changing color from white to brown.
Add washed and sliced mushrooms to the pan. Cook on medium heat until the mushrooms are cooked through and soft to touch.
Add chopped water chestnuts. Mix well.
Add 2 tablespoons of Marinade. Mix well.
Add cooked tofu, cilantro and scallions. Mix well. Remove once warm, and put aside.
Mix ingredients for Peanut Sauce to creamy consistency. Set aside.
To serve, add few tablespoons of Taco Filling into the center of a lettuce leaf. Drizzle peanut butter sauce on top along with some roasted salted crushed peanuts.