The Gingerbread House is the famous home of the evil hag from the fairy tale, "Hansel and Gretel."
Unwilling to return a book of fairy tales to the New York City Public Library, Slimer hid it underneath the Ethereal Solidifier. In a few hours, the Solidifier corporealized the Enchanted Forest and Gingerbread House. It manifested somewhere in Manhattan. The Ghostbusters arrived and investigated the forest.
Slimer was the first to realize the Gingerbread House was edible. Wood was made of gingerbread, the front door knob was rock candy, and some flowers on the window sill were cotton candy. Everyone but Peter Venkman took a taste of the house. The house was not too fond of being snacked on and changed into a monstrous form. After stepping in some taffy, the Ghostbusters opened fire and disintegrated it with relative ease. Egon Spengler took a sample of the charred gingerbread for further analysis. He confirmed the molecular structure didn't match that of normal gingerbread but was a lost to explain how it smelled and tasted like gingerbread until Slimer's part in it was revealed. 
- ↑ Egon Spengler (2009). The Real Ghostbusters - "Once Upon a Slime" (1987) (DVD ts. 12:04-12:07). Time Life Entertainment. Egon says: "Strange... the molecular structure doesn't seem to match that of normal gingerbread."