Grease a madeleine tray and place 1 sage leaf into base of each mould and set aside

Preheat oven to 180°C

Place Parmesan cheese into mixing bowl and grate for 10 seconds at speed 9 and set aside in small bowl

Place butter into mixing bowl and melt for 1 minute at 90°C on speed 2

Add polenta, flour, soda, salt and pepper and mix for 5 seconds at speed 5, scraping down sides of mixing bowl with spatula

Add egg, buttermilk and reserved Parmesan, then mix for 8 seconds at speed 4, or until smooth

Spoon 1 tablespoon of polenta mixture into each mould and bake for 8-10 minutes (or until a wooden skewer inserted into the centre of each madeleine comes out clean) in middle rack in oven

Rest for 5-10 minutes, then gently ease each out of the mould