Poppy seeds are hard-to-explain delicious—floral but gritty, welcome and yet peskily ever-present (especially between your teeth). Their taste is earthy, elemental. Sweet filling made from poppy seeds looks like potting soil; indeed, the actual seeds enter this world in the bellies of flowers. The crunchy, nutty specks are as much a source of texture and color as they are of flavor and, even more so, of identity. Poppy seeds are a motif in the great foods of the Jewish canon, in hamantaschen, flódni, and yeast-dough strudels, on challahs, bialys, and bagels, and are eaten in places, from Alsace, France, to deep Russia, where Jews once thrived. Though these communities are diminished or gone, that sprinkling of black seeds on your lap, in the bag your everything bagel came in, in the trendy halva you smuggled home from Israel, are lingering reminders of who we are, a trail of where we came from.

Gabriella Gershenson is a food writer and editor based in New York. She writes the Bits and Bites column for the Wall Street Journal.