Via: Martin Poole
Pare the zest from one of the oranges and put in a small pan with the juice of one clementine, the sugar, spices and 100ml water.
Stir over a low heat until the sugar has dissolved. Increase the heat and boil rapidly for 5 minutes or until syrupy. Set aside to cool slightly before discarding the spices and orange zest.
With a serrated knife, remove the peel and pith from the remaining oranges and clementines. Slice into thin rounds, adding any juices to the syrup. Serve on a platter, drizzled with the warm syrup and scattered with the pistachios.