Stir-fried Pork and Potatoes

Ingredients

• 200 g lean pork
• 1 tbsp sugar
• 1/2 tsp salt
• 1/2 tsp white pepper
• 1/2 tbsp tapioca starch, or cornstarch
• 1/2 tbsp soy sauce
• 1 tbsp mushroom-flavored dark soy sauce
• 2 potatoes, peeled and cut into thin slices
• 2 tbsp cooking oil, more for deep-frying potato slices
• 2 garlic cloves, chopped
• 1 stalk leek, cut lengthwise into 5cm length
• 1/2 cup hot water