• Preheat your oven to 190°C (170°C for fan-assisted ovens, Gas Mark 5 or 370°F) and line a couple of baking trays with greaseproof paper. Set aside.
• In a large bowl, cream together the butter/margarine and sugar until light and fluffy. Sift in the flour and cornflour to create a paste-like dough.
• Take a small amount of your dough (about the size of a ping-pong ball) and roll into a sausage shape. Place onto your prepared baking sheets and score with a fork. Repeat with the rest of the dough, leaving space between each.

  Alternatively, you can pipe the biscuits using a star nozzle and a piping bag, if you prefer.
• Bake in your preheated oven for 10-12 minutes, until the biscuits have spread a little, look dry and have a slight golden colour. Leave to cool on the baking tray.

To Finish and Fill

• Once your biscuits have cooled, melt your chocolate over a bain-marie or in short blasts in a microwave. Dip either end of your biscuits in the chocolate before placing them back onto the greaseproof paper. When all biscuits are coated in some chocolate, pop them in the fridge to set.
• While the chocolate is setting, in a large bowl, mix the butter/margarine and sugar until light and fluffy to create your buttercream filling. Pipe or spread a small amount of buttercream onto a biscuit before sandwiching another biscuit on top. Repeat with the remaining biscuits and buttercream.