This is a very simple and common dish in Shojin Ryori (Classical Japanese Cuisine).

What You Will Need
nasubi (Japanese eggplant)
vegetable oil or grapeseed oil
miso
sake (rice wine)
(optional) sansho pepper or gomasio(sesame salt)

Note:
Japanese style eggplants are long and thin with a dark purple skin. They are very flavourful and the skin is very soft and wonderful to eat. They do not need to have the bitterness soaked away in brine as do the large eggplants commonly used in the West. Other varieties of eggplants may also be used.

What To Do Now
Wash and dry the eggplant and cut in half lengthwise.

Score both the skin side and the flesh side of the eggplant with the point of a knife in a crisscross pattern.

Brush the eggplant lightly with oil on both sides.

Thin the miso with sake. If a coarse miso is being used it can be ground in a suribachi (mortar) until smooth.

Grill or broil the eggplant first on the skin side and then on the flesh side until slightly underdone.

Remove from the broiler, or grill, and evenly spread the miso over the surface of the meat side only.

Return to the broiler and cook until the surface is lightly browned, being careful that the miso does not burn.

Serve with a garnish of sansho pepper or gomasio sprinkled over the miso.)