Painting of the legend of the Baker of Eeklo, late 1500s, by Cornelis van Dalem (I also have seen mentions of Jan van Wechelen?). Collection of Muiderslot Castle on the Zuider Zee in the Netherlands.
“Legend has it that people with heads they did not like went to Eeklo (Flanders), where the village bakery would rebake their heads in its ‘great and glowing oven.’ Once a doctor had established what was wrong, the baker’s assistant would chop the head off, putting a cabbage on the neck to stanch the flow of blood. The head was then kneaded, sprinkled with flour, and rubbed with wondercream [sometimes egg yolk], before being purified by the heat of the oven and replaced.” [from British Medical Journal 2003 March 29; 326(7391): 692.]
Thus children were admonished not to complain about their looks.