My friends Kunikatsu and Mikako Seto served us a dead-simple dish of eggplant simmered in a whisper of broth. The heavenly broth was flavored with konbu, local mackerel fish sauce, and sake. Eggplant and fish sauce are a perfect match, since the bland eggplant always seems to want some punch. In the winter, Japanese leeks (negi) or thinly sliced daikon are used in place of the eggplant. You can also simmer chunks of peeled potatoes in the leftover simmering juices.
From Preserving the Japanese Way: Traditions of Salting, Fermenting, and Pickling for the Modern Kitchen, by Nancy Singleton Hachisu/Andrews McMeel Publishing, LLC
Slice the eggplants down the middle lengthwise and cut crosswise on the diagonal into 5/16-inch (7-millimeter) pieces. Discard the tip ends. Soak the eggplant pieces in a bowl of cold water to remove the bitterness while you prepare the simmering water and six small bowls.
In a medium pot over medium-high heat, bring the konbu and 2 cups water to a simmer. Flavor the broth with the fish sauce and sake and simmer for 1 minute. Working in batches (a total of 3), throw in a large handful of eggplant and a pinch of slivered yuzu peel. As soon as the water comes back to a rollicking boil, skim out the eggplant and yuzu slivers into each of the prepared bowls and ladle in a tiny bit of the broth. The eggplant should be half raw and pleasantly springy. The broth should have a faint whiff of the sea. Give each person a pair of chopsticks and serve hot as a quick afternoon pick-me-up snack. Cook more as you go.