To make the gingerbread dough, put the butter in a large bowl.
In a saucepan, stir together the sugar, syrup, spices and ginger and bring to the boil. Add the bicarbonate of soda (it will puff up) and pour the hot mixture over the butter. Stir until the butter has melted.
Beat in the egg and slowly blend in the flour. It will look as though there is too much flour but it will blend in.
Knead the dough in the bowl until smooth and cut into quarters. Wrap each piece in clingfilm. Roll out a quarter of the dough at a time to make the biscuits.
Roll the dough out between two sheets of baking parchment, to about 3mm thickness. Use a variety of Christmas cutters to stamp out about 50 biscuits of varying sizes. We used snowflake cutters from 12cm across down to 4cm. Remember you will need two of each size, to sandwich together. Re-knead and re-roll the trimmings.
Lay the biscuits out on baking sheets, lined with baking parchment. Stamp out the centre from half the biscuits to create the space for the conserve. We used a 2 1/2cm and 1 1/2cm round cutter. Chill the biscuits for a good hour before baking.
Heat the oven to 170C, 150C fan, gas 3. Bake the biscuits in batches until golden and crisp. They will take between 7 and 10 mins, depending on size. Cool on a wire rack.
While the biscuits are cooling, roll out the fondant icing on a surface dusted lightly with icing sugar and stamp out 6 or 7 snowflakes, using the same cutters. Stamp out the centres, using the same round cutters. Brush the top biscuits with a little conserve and lightly press on the matching icing.
Brush all the base biscuits lightly with conserve and press on the top biscuits. You should now have about 25 snowflake biscuit sandwiches of various sizes, some iced with fondant and some plain.
Put the Royal icing sugar in a bowl with 40ml of cold water. Gradually beat the icing until it forms a stiff but pipeable paste. Spoon into a piping bag with a small nozzle and pipe or drizzle icing across most of the biscuits to resemble snowflakes. Leave the icing to set for 10 mins. Fill the biscuit centres with various flavours and colours of Bonne Maman Conserve. Store the biscuits in airtight containers until ready to use.
To serve, arrange the biscuits in a generous wreath on a large white board and take to the table for Christmas tea.
If you don't want to pipe the icing, spoon it into a strong plastic food bag and push it down towards one corner. Twist the bag and snip a small opening from the corner. Squeeze out the icing and simply drizzle it across the snowflakes.
