You and your family can shed new light on a holiday baking tradition with this elegant gingerbread lantern.
To make the gingerbread, heat the oven to 350º. In a large bowl, beat the butter and the sugar with an electric mixer on medium-high speed for about 5 minutes. Stir the baking soda into the water to dissolve it, then add this to the butter mixture. Stir in the molasses. Combine the flour, ginger, allspice, and cinnamon in a medium bowl, then stir the dry ingredients into the butter mixture a little at a time. Cover the bowl with plastic wrap and chill it for 1 hour.
Prepare the by rolling out the chilled dough to a 1/4-inch thickness on a large piece of parchment paper, sprinkling on some flour if the dough sticks. Then, using a 4- by 7-inch piece of cardboard as a template, cut 4 rectangles from the dough, removing any scraps. Transfer the gingerbread pieces to a cookie sheet by topping them first with a piece of parchment paper the size of the cookie sheet, then with the inverted cookie sheet itself. Quickly flip everything over, then remove the top piece of parchment paper.
To install the windows, use cookie cutters dipped in flour to cut and remove a few shapes from each gingerbread piece. Unwrap candies in similar colors (you'll need about 2 to 3 for each 21/2-inch cutout) and place them in doubled freezer bags. Hit them gently with a hammer to crush them, then generously fill each cutout with crushed candy. Bake the gingerbread for 12 minutes, then let it cool for at least 1 hour. (The candy windows will be extremely hot! Do not touch them until they have cooled completely.)
Finally, construct the lantern by beating together all of the icing ingredients in a small bowl with an electric mixer on low speed until blended, then increase the speed to high and beat for 4 to 5 minutes or until stiff peaks form. Using a pastry bag or a plastic bag with 1 corner cut off, pipe icing along the long edges of 2 of the walls. Assemble all 4 walls vertically on a platter or a piece of foil-covered cardboard, filling in any gaps and decorating the edges with more icing. Allow the icing to dry overnight. Set the lantern in a safe spot, then place a small candle inside and light the wick (parents only).