Preheat the oven to 200°C. Place the duck legs on a rack in a roasting tin, prick the skin all over with a fork, then sprinkle with salt and 1 teaspoon of the five-spice powder.
Roast the duck for 50 minutes until crispy and cooked through. Spread the apricots in a shallow ovenproof dish (reserving the juice), sprinkle with the sugar and bake in the oven for the last 15 minutes of the duck cooking time until lightly caramelised.
Remove the duck to a warmed serving plate and pour off all but 1 tablespoon of fat from the tin, then place the tin on the stove. Stir in the flour and cook, stirring, until well browned. Add the stock, vinegar and reserved apricot juice and cook, stirring, until thickened. Stir in the honey, ginger and ¼ teaspoon of the five-spice powder.
Serve the duck with the hot apricots and spoon over the fruity, gingery sauce.