Sure you could just buy a kit from the store, but it's much more fun and fragrant to make on yourself using this Gingerbread House recipe with royal icing to hold your construction together. It's one of our favorite Christmas traditions!
Cream butter and sugar in a large bowl of a stand mixer fitted with a paddle attachment. Add the molasses and mix well.
Add the cinnamon, ginger, cloves, salt, and 1 cup of the flour, mixing until combined. Continue to add the remaining flour, 1 cup at time, alternating with the water until a thick dough comes together. Be sure to stop and scrape the bottom and sides of the bowl partway through. The dough should be stiff enough for rolling right away, although you can chill it in the fridge for up to 3 days, if desired.
Roll out the dough on parchment paper to ¼-inch thickness. This dough tends to stick even to floured counter tops, so parchment paper is pretty much crucial to your success. Be sure to flour the top of the dough and your rolling pin periodically so it doesn't stick.
Place the pattern shapes on the gingerbread dough and cut out individual pieces using a pizza cutter for longer lines and a small, sharp knife for smaller shapes like doors or windows. Re-roll the dough scraps as needed until you have cut out all the pieces for your houses. If your dough is ¼-inch thick, you should have just enough dough for 2 basic houses. Carefully transfer the pieces to baking sheets lined with parchment paper.
Bake on parchment paper on two to three large baking sheets. Baking time depends on thickness of each piece, but generally the larger roof, front, and back pieces will take about 25 to 30 minutes. Smaller pieces like the side walls and doors will take around 20 minutes. The edges will be lightly browned when done and the pieces may still feel somewhat soft, but will continue to harden as they cool.
Cool pieces completely before decorating. The gingerbread pieces can be made a week in advance and stored on the counter. Or you can freeze them for 2-3 months and thaw at room temperature before decorating.
Combine the powdered sugar, egg whites, and cream of tartar in a large bowl. Beat well for 7-10 minutes until thick and forming stiff peaks. The icing should be pipeable. If needed, add additional powdered sugar to thicken the icing, or a little water, a couple teaspoons at a time, to thin.
Cover a sturdy board or surface with aluminum foil. "Glue" the front, sides, and back of the house together by piping thick lines of icing onto the pieces and holding them in place, propping them with canned goods if needed until the frosting sets, usually within just a few minutes. This is usually enough to continue decorating. The icing will continue to harden overnight.
Add the roof after the walls have set up a bit and hold it in place for a couple of minutes until it seems solid. It's best to wait 10-20 minutes for the house to set up before proceeding with decorating.
Once the house seems fairly sturdy, go ahead and decorate with remaining icing and candy.
Display your finished house!
*For lighter gingerbread, use ⅓ cup light corn syrup, ⅓ cup molasses, and ⅓ cup honey in place of the full 1 cup of molasses. For the lightest possible color, use all corn syrup instead of molasses and honey.
Meringue Powder Alternative to egg whites: Rather than using egg whites, you can use the same amount of powdered sugar with ½ cup of meringue powder and ½ cup of water. Just combine them in a large bowl and beat until stiff peaks form, adding additional water to thin out the icing as needed to it's nice and pipeable.