Slice the aubergines in half lengthways keeping the stems intact.
Score the flesh side diagonally to form a diamond pattern.
Heat 0.5cm of oil in a pan and fry aubergines cut-side down for three minutes until browned.
Turn aubergines over and fry for two minutes until soft.
Drain the aubergines on kitchen paper.
Preheat the grill to medium.
Mix the miso, sugar, grated ginger, soy sauce, and mirin in a bowl.
Place aubergines cut-side up on a baking sheet and spread with miso topping.
Grill until the topping browns and bubbles slightly.
Scatter sliced spring onions over the aubergines and serve.