Grilled white miso eggplant

Name: White miso eggplant
Prep time: 5 min
Cook time: 30 min
Total time: 35 min
Yield: 2-3
Ingredients: 2 medium-sized eggplants (Japanese eggplants work best, but regular can also be used); 2 tbsp white miso paste; 1 tbsp mirin (Japanese sweet rice wine); 1 tbsp sake (or dry white wine); 1 tbsp sugar (can adjust based on preference); 1 tbsp soy sauce (optional, for extra flavor); 1 tsp sesame oil; 1-2 tsp vegetable oil (for grilling); 1 tbsp sesame seeds (for garnish); 2 spring onions, thinly sliced (for garnish)