Place the butter, sugar, golden syrup and treacle in a medium saucepan over a low heat and stir until melted. Remove from the heat.
Add the ginger, cinnamon, cloves, allspice and bicarbonate of soda and whisk until smooth. The mixture will foam up a bit.
Add the flour and stir with a wooden spoon until well combined and no dry patches of flour remain. Wrap the dough in clingfilm or an environmentally friendly alternative and refrigerate for a couple of hours until it is firm enough to roll out.
Roll the dough out either on a lightly floured surface or between two sheets of baking parchment to about 3-5mm thick, depending on how thick you want your cookies.
Cut out as many shapes as you can with your choice of cookie cutters. Bring the scraps together into a ball and re-roll to cut out more shapes.
Place them well spaced apart on a couple of baking sheets lined with baking parchment. (They will spread a little as they cook so make sure they have a bit of room).
Place the trays in the freezer for 15 minutes until firm. Meanwhile preheat the oven to 180°C/350°F/gas mark 4.
Bake the cookies for 8-12 minutes depending on whether you want them soft or crunchy and how big they are. Little ones will cook more quickly than larger cutouts. The cookies will still be very soft but will firm up as they cool. I bake mine until they are beginning to brown around the edges.
Leave the cookies to cool on the trays for a couple of minutes then carefully transfer them to a wire rack and leave to cool completely.
Once the cookies are cold make the royal icing. Place the sifted icing sugar in a bowl and stir in the lemon juice and aquafaba. The icing should be thick but pourable. If you drizzle some back into the bowl the pattern should disappear after 10 seconds or so. If it is too thick stir in a drop more lemon juice, and if it is too runny add some extra sifted icing sugar.
Transfer the icing to a piping bag fitted with a small round writing nozzle and decorate the cookies as you like.
Leave the decorated cookies to dry flat for a couple of hours before storing in an airtight container.