Pre heat the oven to 180°C gas 4.
Mix the salt, pepper and five spice together well.
Rub over the duck legs both sides and leave for 30 minutes (best overnight)
Heat an ovenproof frying pan, add the legs skin side down.
Leave to brown for 2-3 minutes, then place in the oven.
Cook for 30 minutes, then turn over and cook for a further 30 minutes, or until cooked but not overcooked. When cooked remove, cover loosely with fill and rest for 30 minutes minimum.
Meanwhile place the sugar, water, onion, ginger, lemon grass puree, into a stainless steel saucepan and bring to the boil, then simmer for about 5 minutes.
Add the rhubarb and bring back to the boil, once simmering cook until soft then leave to cool. Then stir in the olive oil.
Serve the duck legs with the relish and salad.