Set the oven up with the main rack in the center, height-wise. Turn the broiler on high.Cut the eggplants in half lengthwise and then score the eggplant flesh with a sharp knife in a one-inch grid. So you now have eight half eggplants all scored.Line them, skin side down, on a sheet pan and brush them with the olive oil. Broil the eggplants for five minutes.While the eggplants are broiling combine the mirin, soy, pure maple syrup, and miso in a small bowl and whisk well to combine it all and break down the miso.Once the five minutes have elapsed remove the eggplant from the oven and spoon the maple and miso mixture evenly all over the flesh side of the eggplants, reset the oven to bake/roast at 350F (from broil), and bake them for 1 minute.Remove from the oven, sprinkle with sesame seeds and serve.