Shanghai Home-Style Aubergines

Name: Shanghai Home-Style Aubergines (Jia Chang Qie Zi 家常茄子)
Cuisine: Chinese
Ingredients: 4 tbsp stock or water; Salt; 1 tsp caster sugar; 1 spring onion, green parts only, finely sliced; A few slices of peeled ginger; ½ tsp dark soy sauce; 300 ml cooking oil; 1 decent-sized aubergine (300 g); ½ tbsp light soy sauce