Preheat the oven to 450°F. Line a baking sheet with paper towels. Using a sharp knife, make shallow crisscross cuts into the cut sides of the eggplants. In a large pan, heat 1/8 inch of vegetable oil over medium-high heat until hot but not smoking. Working in batches to avoid crowding, carefully lightly fry the eggplant for 90 seconds on each side, then drain on the paper towels.
Spread about 3/4 tablespoon sauce on the cut side of each eggplant and place it, cut side up, on a rimmed baking sheet. Roast the eggplant until tender and the miso has lightly caramelized, 10 to 15 minutes. Cut each half into thirds, sprinkle with shiso and sesame seeds, and serve.