What is a famous literary example of an object that triggers flashback?

In literature, the famous example of an object that triggers a flashback is the madeleine in Marcel Proust's "In Search of Lost Time." When the protagonist dips the madeleine, a type of French pastry, into his tea, it instantly transports him back to his childhood memories of visiting his aunt in the countryside. The taste and smell of the madeleine evoke a flood of vivid recollections and emotions, leading him on a journey of introspection and nostalgia.