Heat oven to 200C/fan 180C/gas 6. Melt the butter, sugar and syrup in a pan. Mix the flour, bicarbonate of soda and ground ginger into a large bowl, then stir in the butter mixture to make a stiff dough. If it won’t quite come together, add a tiny splash of water.
Cut out the template (see below to download). Put a sheet of baking paper on your work surface and roll about one quarter of the dough to the thickness of two £1 coins. Cut out one of the sections, then slide the gingerbread, still on its baking 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.
Pick out the most intact flaked almonds and gently poke them into the roof sections, pointy-end first, to look like roof tiles. Bake all the sections for 12 mins or until firm and just a little darker at the edges. Leave to cool for a few mins 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, ideally for a few 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 mins until the icing starts to dry. Dry completely, ideally overnight. To decorate, pipe a little icing along the length of 20 mini chocolate fingers and stick these lengthways onto the side walls of the house. Use three, upright, for the door.
Using the icing, stick sweets around the door and on the front of the house. To make the icicles, start with the nozzle at a 90-degree angle to the roof and squeeze out a pea-sized blob of icing. Keeping the pressure on, pull the nozzle down and then off – the icing will pull away, leaving a pointy trail. Repeat all around the front of the house. Cut the chocolate mini roll or dipped Flake on an angle, then fix with icing to make a chimney. Pipe a little icing around the top. If you’ve made gingerbread trees, decorate these now, too, topping each with a silver ball, if using. 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.