We use two different types of “glue” for our gingerbread houses. The first is simply sugar (white is cheaper, but brown works as well), simply melted until it’s liquid.
As you can imagine, this is very hot and very messy, as evidenced by this video of 2024’s gingerbread assembly:
It’s not the type of glue you want to let your five-year-old handle, but it also sets really fast. It’s really better than super glue in that aspect, and there’s just not another substitute for structural adhesion.
There’s no recipe for melted sugar – just melt it on low and keep it there while you’re working with it. We use a standalone burner/hot plate to keep it in its liquid state while working.
(Cleaning up the burner is hopeless, but the stainless steel pans we used all eventually came cleaning, mostly with hot water.)
The other option is royal frosting, which we use for glue on things like siding or roofing. Because it takes awhile to set, it’s not recommended for structural work unless you’re prepared to brace it for a really long time. For royal frosting, we have a recipe:
Royal Frosting for Gingerbread House Decorations
1/2 cup or approximately 3 egg whites
1/2 teaspoon cream of tartar
1 lb powdered sugar
Using a mixer, slowly combine with a whisk attachment.