In a small pot with water, boil the sugar, the cinnamon stick and the peels of lemon and orange. Syrup will be ready when sugar will be totally dissolved.
In another pot, pour Horio Classic olive oil and let it warm up. Add semolina and simmer it while stirring (in order to just toast it, not burn it). When the grains of semolina darken into a tan color, add the cinnamon powder and put the pot off the heat. Add the raisins and the syrup and stir.
Put again the pot on heat and stir until the mixture becomes homogenized. When ready, put the mixture into a tin. When cool off, remove the halva from the tin and serve.