Combine the ground chicken, onion, breadcrumbs, garlic, lemongrass, cilantro, lime zest, fish sauce and sugar into a large bowl. Incorporate the ingredients well with your hands. Divide and shape the mixture into 6 patties, and then cover and refrigerate them for 30 minutes.
Light a barbeque or preheat a chargrill pan that has been brushed with a little flavored, light oil, such as grape seed or canola.
Grill the patties for 4 minutes on each side or until they are fully cooked through. To serve, layer the burgers on the soft rolls with lettuce, mint, cilantro leaves and chili sauce. These burgers are great with the Spicy Slaw.
Mix together the vinegar, sugar, lime juice, fish sauce, chiles and salt. Stir together until the sugar is dissolved.
Mix together the sugar and rice vinegar, add the carrot and let marinate for 20 minutes. Drain the carrot and add to the cabbage with the celery, onion, mint and cilantro in a large bowl. Add the dressing and toss together. Serve with the burgers.