This is an excerpt from Libre del Coch
(Spain, 1520 - Robin Carroll-Mann, trans.)
The original source can be found at Mark S. Harris' Florilegium
110. DOBLADURA OF MUTTON. You will take a crustless piece of bread and remove the crust , and toast it so that it is not burnt, and set it to soak in the meat broth; and then take fatty bacon and fry it gently until all of the fat comes out; and then gently fry with it an onion, very clean, and cut small; and take a good quantity of toasted hazelnuts, and grind them with the toasted bread that was soaked in the broth; and after grinding it well, blend it with the meat broth, and strain it through a woolen cloth; and then take the meat and make pieces as big as two fingers and gently fry them with the bacon fat; and after gently frying it, mix it with the onion; and then take fourteen egg yolks, and all fine spices, and a little saffron, so that it has the color of the flowers of hiniesta or broom, and beat the eggs very well with the spice, and cast them into the pot to cook with the bacon and with the onions; and cook it long enough to turn quite thick; and when it is cooked, prepare dishes; and [cast] upon them ground cinnamon, and [cast] upon the cinnamon, seeds of sweet pomegranates.
Other versions of this recipe:
DOBLADURA OF VEAL (Libre del Coch)