Line a large baking tray with a silicone baking mat. Pour the liquid maltose onto the mat, place in a 220°C (425°F/Gas 7) oven and allow the maltose to rapidly bubble for 8–10 minutes or until it has achieved a deep golden colour.
Remove from the oven and allow to cool completely. Once the maltose is cold and hard, break it into small pieces and put it into a food processor. Process to a fine powder. Cut a 10 x 15 cm (4 x 6 inch) rectangular hole from an acetate sheet to form a template. You will need to have about a 10 cm (4 inch) border of acetate around the cut-out. Lay the template on a baking tray lined with a silicone baking mat. Put the maltose powder into a medium–fine sieve and sift the powder into the template to a thickness of roughly 1 mm (1/32 inch). Carefully lift the template and repeat: you will need a minimum of 8 rectangles, and you may need to make extra to allow for breakages. Remelt the maltose in a 180°C (350°F/Gas 4) oven for 5–6 minutes until it lightly bubbles. Allow the sheets to cool and store in an airtight container between layers of silicone paper, with silica gel to ensure they don’t stick together.