In a small bowl, whisk together the chili garlic sauce, sesame oil, gluten-free soy sauce, hoisin sauce, vinegar, and sherry. Set aside.
Heat the canola oil or oil of choice in a wok or an extra-large skillet over medium heat.
Add the ginger and scallion whites and cook until the scallion whites are translucent and the ginger is fragrant, about 2-3 minutes.
Add the tofu and cook until just cooked through, about 4-5 minutes, stirring frequently.
Add the chili garlic sauce mixture.
Reduce the heat to simmer and cook for another 3-4 minutes, stirring constantly.
Add the water chestnuts and stir.
To serve- tear large pieces off of the lettuce head and fill each lettuce leaf with the filling.Garnish with sliced scallion greens, red peppers, and peanuts before serving.