Toast the Szechuan peppercorns in a dry skillet until fragrant, about 4 minutes. Cool slightly, and then crush in a spice grinder or mortar and pestle with the salt and five-spice powder until very fine. Rub seasoned salt all over the chicken thighs.
Place in a bowl, cover with plastic wrap and refrigerate for at least 4 hours or preferably overnight.
Bring the chicken to room temperature about 30 minutes before cooking.
Line the bottom of a wok, skillet or heavy pot with a double layer of aluminum foil.
Mix the rice, tea and brown sugar together and mound on the foil. Set a steamer on top, and evenly space the chicken on the rack. Cover and cook over high heat. Hot smoke the chicken until smokey-brown colored and cooked through, about 12 minutes.
While the chicken cooks, whisk the Shao-sing wine or sherry, soy, ginger, and sesame together in a small saucepan. Bring to boil over high heat, remove from heat and steep for 5 minutes.
Brush over cooked chicken.
To serve: Dice the chicken into very small pieces. Toss with the scallions and peanuts in a medium bowl.
Cut the lettuce leaves into 40 squares or triangular scoops.
Place a drop of Sriracha on top of each lettuce cup, and top with about 2 teaspoons of the diced chicken. Squeeze lime juice over the top, and drizzle the remaining soy-ginger sauce over the chicken.
