The act of covering any region with post cum, leaving a thin and shiny film of residue not unlike that of a glazed donut. Most popular practices involve rubbing the penis over the cheek of a female (preferably) until empty and cheek covered. If the female is tan this will further assist in the glazed donut appearance. The pleasurable feeling of recent climax is also similar to the happy sensation resulting from eating large amounts of sugar (glazed donuts); this further bonds the act and term.
"Dude, I was glazing the donut on Janet and totally passed out." or "Jim was glazing the donut and I left a snail trail on the sheets. Pretty nasty"