Preheat oven to 180°C. Grease two oven trays and line with baking paper.

Process butter, icing sugar and tea in a food processor until pale. Add sifted flour and cornflour; pulse until dough comes together, stopping occasionally to scrape down side of bowl. Flatten dough until 1.5cm thick, wrap in plastic wrap and refrigerate 30 minutes

Roll dough between two sheets of baking paper until about 8mm thick. Using the teapot cutter, cut out shapes, re-rolling pastry scraps until all dough is used.

Place teapots on trays 2.5cm apart. Bake 15 minutes or until browned lightly. Stand 10 minutes before transferring to a wire rack to cool.

Melt chocolate in a heatproof bowl over a saucepan of simmering water, taking care not to let the bowl touch water. Cool to room temperature, but still melted. Spoon chocolate into paper piping bag. Pipe a teapot outline on the biscuits. Leave to set.

Meanwhile, to make limoncello icing, stir sifted icing sugar and liqueur in a small heatproof bowl over a small saucepan of simmering water until icing is smooth; cool slightly.

Using a palette knife, spread icing inside chocolate outline. Sprinkle with sugar pearls then sanding sugar. Stand until set.