Wash the kabocha squash thoroughly, cut it in half, and remove the seeds.
Cut the kabocha into bite-sized pieces and steam for 10 minutes.
In a small bowl, mix the eggs, milk, salt, and pepper well.
Place the steamed kabocha in an oven-safe dish and pour the egg mixture over it.
Top with mozzarella cheese and bake in a preheated oven at 180°C (356°F) for 10 minutes.
Garnish with parsley to finish.