In a mixing bowl, stir together the ground pork, shallots, ginger, cornstarch, and 1 tablespoon of the garlic. Heat 2 tablespoons of the peanut oil in a large sauté pan over high heat. Add the pork mixture, pressing it down with a wooden spoon to form a patty; cook without breaking up the meat until the underside is browned, about 4 minutes. Then, break up the pork and continue cooking and stirring until the meat is uniformly browned, 3 to 4 minutes more. Stir in the remaining peanut oil and garlic and sauté 2 to 3 minutes longer. Add the rice vinegar and stir and scrape to deglaze the pan deposits. Stir in the soy sauce, Asian chili sauce, and 2 tablespoons of the hoisin.

To serve, place the tortillas on a microwave-proof plate, cover with a clean dishtowel, and microwave until warmed through, 30 to 40 seconds. In a clean bowl, toss the lettuce mixture with the dressing. Spoon the ground pork mixture down the center of each tortilla. Spoon lettuce alongside the meat. Drizzle on some additional hoisin sauce, garnish with scallions and serve.