Sprinkle a dusting of flour on to a large baking tray. Using wet hands (these work better than floured hands), roll the mixture into nuggets just smaller than a walnut, then roll each gently in the flour to coat lightly. Put on a plate, cover with cling film and refrigerate for one hour, or up to one day, to firm them up (the chilling here is vital).
Put a really big saucepan of lightly salted water on to boil, then reduce the heat to a simmer. Melt the 50g butter in a large frying pan or sauté pan, then take it off the heat. Cook the gnudi in batches by dropping them into the water.
After a couple of minutes they should have bobbed to the surface, so lift them out with a slotted spoon and drop them into the butter. Shake around a little and cover the pan. When all the gnudi are cooked, gently heat them through in the butter.
Serve in warmed dishes, sprinkling with a little more Parmesan and grinding on some black pepper.
Recipe from How To Eat a Peach: Menus, Stories and Places by Diana Henry, published by Mitchell Beazley (£25). Order your copy from books.telegraph.co.uk