Peel and cut yam into small pieces and steam for 45 minutes until soft.

Remove yam from steamer and mash thoroughly with potato masher or a fork. Add sugar, water and about ⅔ of the oil and mix well. Mash yam with a fork until fine.

Pour the remainder oil into a frying pan. Add the yam mixture and stir fry until it comes together for about 15 to 20 minutes.

Set aside to cool and mix with some toasted melon seeds.

Use as filling for making traditional mooncakes.