1/2 eggplant per person
With a sharp knife, slice the eggplants in two lengthwise, then score deeply right around the edge of the flesh and cross-score the cut face to make a criss-cross pattern. This looks good but also makes the eggplant easier to eat.
Brush the cut surfaces lightly with sesame oil. Drizzle mirin over the surface, allowing it to sink into the cuts. Take a little miso paste and, with a knife, smear it across the surface quite thinly, or the taste will overwhelm the dish. Sprinkle sesame seeds on top.
Bake in a medium 375 oven until quite soft, about 40 minutes or so. Serve hot or at room temperature with pickled ginger and a green salad.