Preheat the oven to 200C/400F/Gas 6.
Strip the cooked meat from the turkey, keeping the pieces as large as you can. They will stay juicier that way.
Peel the garlic and add to a pestle and mortar along with a generous pinch of salt. Grind to a paste and transfer to a bowl. Stir in the honey, soy sauce, chilli sauce, ketchup, mustard and a drizzle of groundnut oil. Season with a little black pepper, then add the turkey meat. Toss gently then tip everything into a baking dish. Bake for 20 minutes, or until the meat is glistening.
Meanwhile make the salad. Peel the oranges and grapefruit with a sharp knife, then slice thinly. Toss with the watercress.
To serve, pile the hot turkey onto the salad and serve.