The avocado’s story is thousands of years older than sushi. The Aztecs called it ahuacatl; the tree’s homeland is the south of present-day Mexico, where the traces of its cultivation reach back millennia. Spanish sailors bent the word to their tongues and made it aguacate; the English avocado grew from there. Japan gave the fruit a nickname of its own: mori no batā 森のバター, butter of the forest. It is hard to imagine a kitchen giving a fruit a more affectionate name.

The avocado entered the sushi counter in 1960s Los Angeles, hired as a stand-in for fatty tuna that could not be found. It played the part so well that it took the lead.

In this member of the Philadelphia family, the work is divided three ways: cream cheese lays down the coolness, salmon brings the silk, and avocado sets its buttery softness between them. Three distinct tendernesses, opening one after another in a single bite.

The road from the Aztec garden to the rice of Edo passes through here.