In a large bowl or stand mixer fitted with the paddle attachment, combine flour, cinnamon, ginger, nutmeg, and salt.

In a 2 quart saucepan, stir together molasses, brown sugar, and butte. Cook over medium heat, stirring occasionally, until butter is melted and ingredients are well mixed.

Pour liquid mixture into flour mixture and stir until well blended. Form into a ball and knead until smooth and pliable. The dough will be thick — that’s intentional. Add a tiny bit of water, if needed, to bring the dough together.

Divide the gingerbread cookie dough into two or three portions. Flatten into disks, wrap tightly in plastic wrap, and refrigerate for at least 1 hour, or up to overnight. 

While the dough chills, prepare your house template.

Preheat the oven to 350°F.

Line baking sheets with parchment paper. Lightly flour your work surface and rolling pin, or roll out the dough directly on the parchment.

Roll the dough to ¼ inch thick (slightly thicker is fine for larger houses). Keeping a consistent inch thick measurement helps ensure even baking and sturdy walls.

Place the house template pieces on the dough and cut around them with a sharp knife. Transfer pieces carefully to the baking sheets, leaving space between each piece. Re-roll scraps as needed, lightly flouring to prevent sticking.

Bake gingerbread pieces for 12–15 minutes, depending on size and thickness. You’re looking for pieces that are:

• Firm to the touch
• Lightly browned around the edges
• Flat and evenly baked

If dough puffs slightly during baking, you can prick the bubbles with a fork. We put the slightly bubbled side facing inward on the gingerbread house.

Allow pieces to cool completely on the baking sheets before moving. 

Make the royal icing:

Beat ingredients together in a stand mixer for 5–7 minutes until thick and glossy. The icing should hold stiff peaks.

Transfer icing to a piping bag or zip-top bag. Keep unused icing covered with plastic wrap to prevent drying out, or cover your icing bowl with a damp towel.

Assemble the gingerbread house:

1. Build the walls first
   Pipe a thick line of royal icing along the bottom edge of one wall and press it onto the base. Add adjoining walls, piping icing along vertical seams.
2. Let walls set
   Allow walls to stand for 20–30 minutes before moving on. Royal icing firms quickly but needs time for strength.
3. Add the roof
   Pipe icing along the top edges of the walls and gently add the roof pieces. At this point, I like to put props in place to hold everything steady.
4. Let the structure dry
   Allow the assembled house to dry for at least an hour before decorating. Overnight is even better. By the next day, that frosting will be absolutely dry and stable.

Decorate the gingerbread house and enjoy.