Slice the eggplant in half vertically and then diagonally score the inside in a criss-cross pattern. Your knife should go all the way into the flesh until it hits the bottom skin of the eggplant half although take care not to cut through it.
Place the oil in a large pan over high heat. Put the eggplant halves skin down in the pan, lower to a medium heat and cook until the skin is brown.
Using tongs, turn the halves over and cover the pan with a lid. Cook for 7-8 minutes or until the halves are completely cooked through.
In the meantime, mix the miso paste, mirin, sugar and sake in a bowl. Set aside.
Preheat the grill in your oven to high.
Cover a cooking tray with foil and place the halves on the foil once they have completely cooked through. Brush them with the miso paste mixture and place them under the grill for 3-4 minutes or until the miso starts to bubble and caramelize.
Sprinkle the sesame seeds over the top and serve hot!
