Method:

1. In a Pan, heat oil then add peppercorn and bay leaves. When the bay leaves start to turn brown, add the garlic. 

2. Saute until brown. Then add the onion and fry until translucent. Add the pepper and the sugar, stir briefly to mix, then add the soya sauce and vinegar. Lower heat to medium then add the potatoes and eggplant. 

3. Stir briefly then simmer, covered, around 25-30 minutes for the potatoes or around 35-40 minutes for the eggplant. They should be soft but not mushy. 

4. Add water if liquid level drops too low.