Preheat oven to 400°F (200°C).
Slice eggplants in half lengthwise. Score the flesh in a crisscross pattern without cutting through the skin. Brush with oil and sprinkle lightly with salt.
Place eggplants cut-side up on a baking sheet. Roast for 20 minutes until tender and slightly golden.
Heat a skillet over medium heat. Cook ground meat until browned. Add miso paste, soy sauce, sugar, mirin, and grated ginger. Stir until thick, glossy, and well combined.
Spoon the nikumiso filling evenly over roasted eggplant halves. Brush with optional dengaku sauce if desired.
Broil for 3–5 minutes until lightly caramelized and bubbling on top.
Top with sliced green onions and sesame seeds. Serve warm.