Preheat your oven to 200°C (390°F) or set up a charcoal grill for indirect heat. In a large bowl, prepare the marinade by combining garlic, shallots, lemongrass, fish sauce, soy sauce, honey, sugar, vegetable oil, turmeric, black pepper, and chili. Stir until the sugar dissolves completely for an even flavour.

Clean and pat dry the chicken leg quarters. Make 2-3 shallow cuts in the thickest parts of the chicken to allow the marinade to penetrate. Add the chicken to the bowl, ensuring each piece is thoroughly coated in the marinade. Cover and refrigerate for at least 1 hour, preferably overnight, to maximize flavour.

While the chicken marinates, prepare your grill or oven. If grilling, ensure the coals are glowing but not flaming, with a cooler zone for indirect cooking. For the oven, place a wire rack over a baking sheet lined with foil to catch drippings.

Remove the chicken from the refrigerator and allow it to come to room temperature for 15-20 minutes before cooking. This helps the chicken cook evenly.

Place the chicken on the grill or oven rack skin side down. If grilling, cook over indirect heat with the lid closed for 10-15 minutes per side. If baking, roast for 20-25 minutes on each side. Baste the chicken occasionally with leftover marinade to enhance flavour and achieve a glossy finish.

Increase the grill’s heat or switch the oven to broil for the last 5 minutes of cooking. Flip the chicken frequently to char the skin slightly while ensuring it doesn't burn. The internal temperature should reach 75°C (165°F) when done.

Remove the chicken from the heat and let it rest for 5 minutes to allow the juices to redistribute, ensuring moist and tender meat.

Serve the Gà Nướng hot with jasmine rice, fresh cucumber slices, and herbs like cilantro or Thai basil. Pair with a side of nước chấm (Vietnamese dipping sauce) for added tang and sweetness. Garnish with lime wedges for a zesty touch.