Below is an excerpt from The Medieval Kitchen Recipes from France and Italy by Odile Redon, Françoise Sabban, & Silvano Serventi Translated by Edward Schneider :
How to make an orange omelette (From “Le ‘Registre de Cuisine’ de Jean de Bockenheim, cuisinier du pape Martin V” edited by Bruno Laurioux)
Take eggs and break them, with oranges, as many as you like; squeeze their juice and add to it the eggs with sugar; then take olive oil or fat, and heat it in the pan and add the eggs. This was for ruffians and brazen harlots.
2 tablespoons sugar
2 tablespoons olive oil
Juice the oranges and the lemon. Beat the eggs, add the juice, the sugar, and salt to taste, and cook the omelette in olive oil. Serve warm.
Johannes Bockenheim (or Buckehen) was cook to Pope Martin V and in the 1430s wrote a brief but highly original cookbook recently edited by Bruno Laurioux. This German, who lived at Rome, wrote as a professional, with telegraphic terseness and little detail; yet he was careful to specify the destined consumer of each recipe, pigeon-holed by social class—from prostitutes to princes—or by nationality: Italian, French, German from any of various provinces, and so forth.
Since medieval oranges were bitter, we suggest a blend of oranges and lemons. The sugar and the acidity of the juice prevent the eggs from completely setting, so this is more of a custardy cream that makes an unusual and very pleasant dessert.
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