A pet-de-nonne is a small, airy, deep-fried ball of pâte à choux sprinkled with sugar. Sometimes there’s a sweet creamy filling.
The story goes that they were invented by one Sister Agnès of the historic Abbey of Marmoutier, who accidently dropped a spoonful of choux pastry into a pot of hot fat, and it made a ‘certain sound.’
Image by Žiga assumed (based on copyright claims).