To begin with, remove from the sausage its gut. Crumble it in a frying pan without any seasoning and cook until it is toasted. Then keep going with the preparation of the béchamel sauce: melt the butter in a saucepan, add the flour and then the milk gradually continuing to stir. Once you get a smooth and almost-dense consistency season it with salt, nutmeg and saffron. Keep aside.In a small saucepan heat a little oil and add the leftover rice; mash the rice very well to form the pie. Brown one side then, with the help of a lid, turn it over to brown the other side. Garnish with the sausage crumbs and complete with saffron cream.