
This Thai grilled chicken is packed with classic gai yang flavor from lemongrass, garlic, fish sauce, and soy sauce. The marinade caramelizes beautifully on the grill or in a hot pan, giving you juicy chicken with savory, sweet, and lightly smoky notes.
Trim the tough outer layers from the lemongrass and use the tender inner part only. Add the lemongrass and garlic to a tall container or small food processor with the fish sauce, light soy sauce, dark soy sauce, and brown sugar, then blend until mostly smooth.
Transfer the marinade to a bowl and stir in the oil. Add the chicken thigh fillets and turn well so every piece is evenly coated. Cover and refrigerate for at least 3 hours, or overnight for the best flavor.
Preheat an outdoor grill to high heat, or heat a nonstick skillet or grill pan over high heat on the stovetop. Once hot, reduce the heat to medium before adding the chicken so the sugary marinade does not burn too quickly.
Lift the chicken from the marinade and let the excess drip off, then discard the remaining marinade. Cook the chicken for 5 to 6 minutes per side, turning as needed, until deeply golden and cooked through.
Transfer the chicken to a plate and rest for 3 minutes before serving. Serve with coconut rice, lime wedges, fresh red chili, cilantro, and your choice of dipping sauce such as Nam Jim Jaew or sweet chili sauce.
For the best texture, use boneless skinless chicken thighs and marinate overnight if possible. If you do not have a blender, finely mince or grate the lemongrass and garlic before mixing the marinade. Keep the heat at medium once the chicken hits the pan or grill, since the sugar in the marinade can scorch quickly. Leftovers keep well in an airtight container in the refrigerator for up to 3 days.