madeleine

noun2

1. •
   A French type of small gateau or sponge cake, often shaped like an elongated scallop shell.

   • Madeleine batter can be made in advance and refrigerated. — 2003
2. •
   (figurative) Something which brings back a memory; a source of nostalgia or evocative memories.

   • The Robe was thus fixed in my mind as a symbol, and in my memory as a madeleine, of Jewish evil. — 2001