Proceed as for a simple omelet: beat the eggs as well as the sugar, add salt as well as the juice of the oranges as well as the lemon. Roast in a frying pan in olive oil (**).
(*) Since the medieval oranges were bitter, it is recommended to mix oranges with lemons. The acidity and the sugar prevent the egg from curdling.
(**) in the original recipe: ‘oleum olive’. However, it is mentioned that you can also take fat.