Gelatinous fruit body of Tremella mesenterica
Image: Jean-Pol GRANDMONT https://commons.wikimedia.org
It looks very much as if this receipt is an attempt to imitate the - not edible - species of Tremella fungus long known as 'fairy butter'.
Original Receipt in 'The Experienced English Housekeeper' by Elizabeth Raffald (Raffald 1769)To make Fairy Butter.
TAKE the yolks of four eggs boiled hard, a quarter of a pound of butter, beat two ounces of sugar in a large spoonful of orange flower water, beat them all together to a fine paste, let it stand two or three hours, then rub it through a cullendar upon a plate; it looks very pretty.