Preheat griddle on low.
In a medium bowl, whisk together soy sauce, mirin, minced garlic, minced ginger, sesame oil, hoisin sauce, and oyster sauce. Taste sauce and add spicy ingredients (siracha and red pepper flakes) to your liking. Set sauce to the side.
Add a bit of avocado oil (or cooking oil of your choice) to the griddle. Start sautéing mushrooms, carrots, water chestnuts, and onions. Cook vegetables and mushrooms until about 50 percent cooked through. Then move them to the side of the griddle.
In the open space on the griddle, add a bit more cooking oil. Add the ground chicken and cook while stirring and chopping, just as you would for ground beef.
When chicken is completely cooked through, add it to the vegetable and mushroom mixture and mix to combine.
Spread chicken and vegetable mixture out into a thin layer on the griddle once again. Pour sauce onto the ground chicken lettuce wrap mixture and mix in thoroughly.
When sauce and lettuce wrap mixture is fully combined, remove from the griddle and transfer to a serving bowl.
Allow the mixture to cool for a few minutes and serve with bibb lettuce leaves.
Top with your favorite Asian toppings like siracha, hot sauce, or yum yum sauce. We also like to add a bit of cream cheese to the lettuce leaves before adding the chicken mixture.