Soak a large wooden cooking stick in cold water overnight.
Light the barbecue until the coals are glowing red and turning white.
Combine lemongrass, coriander, garlic, chillies, ginger, lime juice, and 50ml of vegetable oil in a bowl.
Coat the poussins in the marinade and secure them onto the wooden stick using string.
Cook the poussins 30cm above the coals for 30 to 35 minutes, turning occasionally.
Whisk egg yolk, mustard, vinegar, and 250ml of water in a bowl.
Slowly whisk in the remaining 250ml of oil until the dressing is emulsified then season with salt and pepper.
Mix 100ml of the dressing into the sliced red cabbage.
Serve the whole poussins with a side of the red-cabbage salad.