This recipe makes enough gingerbread to fill a half-sheet pan, so, before getting started, sit down with your template and figure out how many trays you'll need, then multiply accordingly (up to a quadruple batch, depending on the capacity of your bowl).
Construction grade gingerbread is sturdy and strong, but still tastes great—crunchy, with plenty of butter, brown sugar, and vanilla, so you can still enjoy nibbling on the leftover debris.
1. For the Dough: Trim a sheet of parchment paper to fit the interior of a half sheet pan. Adjust oven rack to lower-middle position and preheat to 350°F (175°C). Combine brown sugar, cinnamon, ginger, cloves, salt, corn syrup, butter, and vanilla in the bowl of a stand mixer fitted with a paddle attachment. Mix on low until smooth, then sprinkle in flour and continue mixing to form a stiff dough. Turn onto a lightly floured surface and knead until smooth. Proceed immediately, or wrap in plastic and set aside at room temperature until needed, up to 24 hours. (Larger batches should be divided into 14-ounce portions.)
2. Sprinkle prepared parchment with flour, place dough on top, and flatten into a rectangle. Sprinkle with more flour and roll to fit just within edges of parchment, leaving dough about 3/16 inch thick. Using both hands, transfer parchment to a half sheet pan. Cut according to your gingerbread house template, using an X-Acto or paring knife. Leave a narrow border of dough around cutouts to minimize spreading, but trim away larger areas of excess dough to gather and re-roll, or turn into paste (see directions below).
3. Bake gingerbread until dry to the touch and golden brown, about 25 minutes. Immediately cut along pre-scored lines with a sharp knife or pizza wheel. Cool completely in pan, then transfer cutouts to a safe place. Scraps can be nibbled, or ground in a food processor to use in recipes that call for cookie crumbs.
4. For the Paste: Return scraps to mixing bowl and resume mixing on low speed. Begin adding water, 1 teaspoon at a time, until scraps form a stiff but pipeable paste. Thoroughly scrape bowl and beater with a flexible spatula to eliminate lumps, then continue mixing until perfectly smooth. Transfer to a piping bag fitted with a small round tip. Pipe designs, such as fences and railing, onto a parchment-lined half sheet pan and bake until pale gold, about 12 minutes. Cool completely before handlingNew Paragraph
1. In the bowl of a stand mixer fitted with a paddle attachment, combine egg white with half the powdered sugar. Mix at low speed until sugar disappears into a paste, then gradually sprinkle in the rest. Increase speed to medium and beat until smooth and light, about 2 minutes. If too stiff, thin icing with a few drops of water. Use immediately; keep covered tightly in plastic to prevent icing from drying in bowl. Royal icing can be kept in an airtight container at room temperature up to 12 hours.
2. For Coloring: To dye royal icing with gel paste (see note), divide into as many bowls as you wish to have colors. Cover each tightly with plastic. Working with 1 bowl at a time, add 1 drop gel paste to a batch of icing, then stir until fully incorporated before adjusting color with more gel. Cover bowls tightly when not in use.
