This is an excerpt from Du fait de cuisine
(France, 1420 - Elizabeth Cook, trans.)
The original source can be found at
David Friedman's website
66. Again, a ressise which is worth much for making the sick person rest and for strengthening the veins and making him better: and to give understanding to him who should make this ressisse, how it is made and of what it is made, let him have a quart of the best wheat from the best territory which can be gotten which should be so picked over and cleaned that nothing remains except for the grain of the wheat itself as it should be for making communion wafers, and have it milled and ground by a well prepared mill; and, being well and properly ground, let him take it back with him in a good small leather sack. And when he wants to make the said ressisse he should arrange that he has a good sifter or sieve and should put the said flour in and sift it, and he should leave the good and fat bran; and this said bran which remains in the sifter he should put in a fair and clean basin and fair fresh water therein and let him stir it strongly with his hand in the basin; and then let him arrange that he has another fair and clean basin next to the other and then let him take some of the said bran and take and squeeze the handful between his hands over the said other basin and, the said bran being thus squeezed, he should throw it out, and when the said bran has all been thus squeezed and pressed between his hands over the said basin leave what is in the said basin to settle, sit, and rest for a little while; and being well rested and settled, drain off the water which is on top very gently and, this done, there remains the fine flour on the bottom of the said basin; and, this being done, put back in more fair fresh water and stir it with the hand a little or with a spoon until the said flour is mixed with the water, and then cover the said basin with a corner of a fair and clean cloth and put the said flour back to sit and settle again, which will settle to the bottom of the said basin. And while it is settling to the bottom of the said basin take a great quantity of good almonds according to the quantity of the said rescisse which should be made, and blanch, clean and wash them very well and bray them very well in a mortar - and be well advised in this, and in all potages which are for the sick, that the mortar should never smell or taste of garlic - and moisten the said almonds with fair fresh water, and make milk from them and strain it through a good and clean strainer; then put the said milk into a fair and clean pot and put it on the fire to boil, and put in a very little salt. Then gently take the basin in which is the ressisse and pour off the water from the said ressise, and then take this ressise and pass it through a strainer with the said almond milk into a fair silver dish; and, having strained that which it seems that he needs, put it with the said almond milk to boil until the said milk is well thickened, and sugar as is necessary to it. And, when it is sufficiently boiled, he should let the doctor know that the ressisse is prepared so that when it pleases him, it may be brought to the sick person in a fair gold bowl or cup.