Starting on fruit and vegetables now – almost a recipe here.
(…) It is better for cholerics if they are served thus: they are cooked in the juice of quinces or pomegranates or sour grapes, or seasoned with the juice of lemons or with almond oil or the oil of unripe olives. But for phlegmatics thus: they are boiled in water and afterwards pressed and served with mustard, pepper, celery and mint and more usefully given, because the heat of these condiments tempers them and generates warm digestive juice, and their condiment is also (suitable) with quinces and other things described above (…) It also has an action that is fitting to medicine. Those (gourds) that are wrapped in dough and roasted, and the juice found inside the crust given to drink, mitigate the heat of the fever and extinguishes it, especially if it is given as a drink with cassia fistula, violet, sugar, and manna. (…)
Isaac Iudaeus de diaetis universalibus et particularibus, originally written in Arabic in the late ninth or early tenth century, was translated and adapted by Constantinus Africanus in the late 11th century and circulated widely in Italy and beyond soon afterwards. While the original applies to a different context, it is still reasonable to use it as a guide to the advice that Siculo-Normans would have found useful. It is an open question how much the original was altered in translation – I cannot say since I read no Arabic. However, the extensive reference to eating pork suggests that some alterations took place.