Place a large saucepan over a medium heat and add in the golden syrup, sugar and butter. Melt the mixture down until the butter has melted and the sugar is completely dissolved. Take off the saucepan of the heat and stir through the cream and spices. Add the baking soda and flour a little bit at a time, mixing with a wooden spoon until you have mixed it all through. Work the dough together until you have a loose mixture. Cover and leave in cool place overnight and the next day you should be left with thick dough.
Preheat the oven to 400°F. Flour a work surface and roll out the dough to the thickness of about a quarter (25 cent). So basically as thin as you can because you want the gingerbread to rise only slightly so they will be nice and crisp when it is cool.
Cut out the templates. Put a sheet of parchment paper on your work surface and roll about one quarter of the dough to the thickness of two Quarters (25 cent). Cut out one of the sections, then slide the gingerbread, still on its parchment paper, onto a baking sheet. Repeat with remaining dough, re-rolling the trimmings, until you have two side walls, a front and back wall and two roof panels. Any leftover dough can be cut into Christmas trees, if you like. Add boiled sweet into the center of the windows and bake all the sections for 10-12 minutes or until firm and just a little darker at the edges. Leave to cool for a few minutes to firm up, then trim around the templates again to give clean, sharp edges. Leave to cool completely.
Put the egg whites in a large bowl, sift in the icing sugar, then stir to make a thick, smooth icing. Spoon into a piping bag with a medium nozzle. Pipe generous snakes of icing along the wall edges, one by one, to join the walls together. Use a small bowl to support the walls from the inside, then allow to dry for at least a couple of hours.
Once dry, remove the supports and fix the roof panels on. The angle is steep so you may need to hold these on firmly for a few minutes until the icing starts to dry. Leave to dry completely, overnight is best.
Using the icing, stick sweets around the door and on the front of the house. Use any remaining icing to decorate the house. Pipe a little icing around the top. If you’ve made gingerbread trees, decorate these too. Dust the roof with icing sugar for a snowy effect. Lay a winding path of sweets, and fix gingerbread trees around and about using blobs of icing. Your gingerbread house will be edible for about a week but will last a lot longer if you just want to use it for decorative effect.