Recovering the Forgotten Art of Making Lem Peng
By Dr. Ong Jin TeongFebruary 2024 FEATURE
LEMPENG, LEN PEN or leng peng? However you may identify it, this traditional Penang Chinese New Year delicacy is now virtually extinct. “Lem Peng” was described as a “light as air” biscuit by Yeap Joo Kim in her book Penang Palate. In an interview, Lim Bian Yam described “leng peng” as a type of crispy but fluffy cookie that “melts” upon contact with the tongue. To avoid confusion, I shall spell it as lem peng, different from the Malay lempeng. I have not seen or tasted lem peng before, but I am told it looks like part of a small nutmeg and tastes like a more refined Japanese rice biscuit.
My quest to find out how to make lem peng started more than 10 years ago after my wife and her cousin, Kee Loon Kim, managed to put together a good hand-written note for preparing lem peng. Loon Kim has only seen it made in the Kee ancestral home in Sungai Bakap in her younger days.
In my attempt, I realised that recreating this treat the traditional way would be a great challenge because of the long, complex and laborious process involved. I was introduced to Aunty Ai, who used to make lem peng for a living, and found at least six recipes for preparing lem peng. In the recipes, the sugar is measured in tahil, and the coconut santan is measured by the number of coconuts used. The rice is measured in gantang or chupak. It has to be ground with water in a cheow bo (traditional granite grinder) and placed in a mee-hoon thay (recycled cotton bag used to transport flour) to drain away the water.
The easy part was mixing the ingredients into a dough. Then, the dough has to be steamed and kneaded with the sugar. However, some recipes require sugar to be added before steaming. But how do you steam one chupak of rice, not to mention one gantang!  How long then should the rice be steamed?
Then, the dough has to be pounded. One recipe suggests pounding it in a large lesung; another uses a marble lesung; the third recipe recommends using a wooden pestle with a very large lesung. That is not all, some recipes suggest pounding till the dough is less sticky, while others recommend that the dough be pounded till it is sticky. I went with “less sticky”.
Pounding even one chupak of dough is no mean feat; one reason why the famed chef, the late Lim Bian Yam, said lem peng was very hard to make. His method was to roll the dough into sheets after pounding, but all my other recipes say that the dough should be steamed first. More confusing is that one recipe adopted a common traditional Malay/Nyonya practice of steaming a quarter of the kneaded dough and then kneading the cooked dough (ibu) with the rest.
The next step in the preparation of lem peng is the division of the dough into small balls or chanai. These marble-sized balls are then flattened and dried in the sun—what seems like a straightforward process. Unfortunately, most of the recipes do not mention how long they have to sun. Plus, if it is cloudy or rainy, the whole batch of the lem peng has to be discarded! That could explain why lem peng costs much more than other CNY delicacies.
One recipe implies that lem peng can dry in a day when laid out on a nyiru (a large bamboo winnowing tray); individual pieces have to be turned over regularly to ensure that the drying is uniform and the nyiru has to be moved during the day to catch the sun.
The dry lem peng is then stored separately in batches and baked when required. Before baking, a sample lem peng is broken into two and toasted on open charcoal fire to check whether it will puff up. If it does not, the whole batch is thrown away.
Lem peng is traditionally baked in a large bok kang (clay pot) over a charcoal fire for 10 to 15 minutes until golden brown. The clay pot is filled with sand and covered with paper, and the lem peng is placed over the paper. According to Aunty Ai, a brass pan is placed over the clay pot and burning charcoal is placed on it so the lem peng is heated from above and below.
Traditional vs. New Appliances
My wife and I tried pounding a modest amount of the lem peng dough in our 27cm diameter lesung, with a 27cm-long anak (pestle) that weighs more than 2kg. It was hard work since the dough was very thick and sticky.
In one of our visits to the Kee Familyʼs ancestral home in Sungai Bakap, we were shown the remains of a lesung kaki, operated by using one leg (kaki in Malay), which I think would ease the process of making the lem peng dough. It is operated by stepping on the other side of the lever, down into the hole on the left of the lever, to lift up the pestle. When the pestle reaches its maximum height, the leg is moved away from the lever so that it drops onto the mortar, pounding the dough.
I also came across a large clay pot in the garden, with plants growing in it, sitting atop a large hung lor (stove).
Traditionally, glutinous rice was grounded using a cheow bo, but when I talked to Aunty Ai, she showed me an electrically operated rice grinder. Today, we can use ground glutinous rice readily available in the market. However, the correct amount of water has to be added to reconstitute the drained wet rice. A good food processor with a high-capacity motor like a Thermomix can also be used to grind the rice finely and to knead and pound the dough.
Baking lem peng is probably the least of our problems since ovens today come with good temperature control compared to the hung lor and clay pot.
Now, the challenge is to get all the steps explained and done correctly, and voila, we should have lem peng!
-  One gantang is equivalent to one gallon. One chupak is ¼ of one gantang.
Dr. Ong Jin Teong
is the author of two award-winning books —Nonya Heritage Kitchen: Origins, Utensils, Recipes and Penang Heritage Food: Yesterday’s Recipes for Today’s Cook. Following his retirement as a Nanyang Technological University’s College of Engineering professor, he lectures, conducts classes, writes books and articles on Nyonya cooking and food heritage, and runs the occasional supper club.