Ultimate indulgence mirror glaze cake recipe

Orange-flavoured génoise, covered in a chocolate glaze and layered with a salted caramel cream – I just had to include salted caramel in this recipe as it's one of my favourite fillings. For this recipe you will need 2 x 20cm/8in springform cake tins, a large heatproof bowl (about 3 litres/5¼ pint capacity), an electric whisk or freestanding mixer, a 20cm/8in cake board, a wire rack that fits in a large baking tray, a sugar thermometer, cocktail sticks, a piping bag fitted with small star nozzle