Mix ground chicken with soy sauce, sugar, minced garlic, lemongrass, sesame oil and scallions. Form into patties. Grill or pan-fry ~7 minutes per side until cooked (165?F). In last minutes, baste each burger with hoisin sauce. Serve on toasted sesame buns spread with sriracha-lime mayo, and top each burger with a crunchy sesame slaw (toss shredded peppers, snow peas, jicama with rice vinegar, a bit of sugar, soy, sriracha and sesame oil).