Buster Keaton’s Recipe For His Famous Pork Pie Hats (in his own words):
1 Stetson Hat
3 Heaping Teaspoons of granulated sugar
1 Teacup Warm Water
Mix water and sugar. Wet the top and bottom of the brim. Smooth it out on a clean, hard surface. Allow to dry until stiff.
"I did the early ones myself myself, always - and then I trained my wife."
(The first one was created in 1917 for “The Butcher’s Boy”)