Mooncake biscuits are little sweet snacks which are like the outer layer of the mooncake. Unlike the traditional baked mooncakes, these biscuits are usually made without filling and are much thicker. They are also nicknamed doll biscuits, a direct translation of its Chinese name, 'gong zai beng'.
History of mooncake biscuits
The origins of doll biscuits are actually from the traditional baked mooncakes. Before making the labourous mooncakes, bakers will usually prepare the dough for the skin and bake unfilled mooncakes. It is to test the texture of the dough and the heat of the brick oven. These unfilled mooncakes were then made into the shape of piglets earning them the nickname piggy biscuits. They were often given as gifts to customers who bought the traditional mooncakes. Over the years, they are made into shapes of Buddha, butterfly or goldfish besides others.
Golden syrup, you need to know this!
This is one of the main ingredients when making mooncakes. Golden syrup is inverted sugar made by refining sugar by treating it with acid.
To make your own homemade syrup, just combine sugar, water and lemon! It is really that simple and it can be made few days in advance. Store it in an air-tight container at room temperature.
Just be careful with the mixture during cooking as it tends to rise. Therefore, using a pot that is deep is highly recommended.
Do not worry about this syrup tasting too citrusy because it is not be even noticeable. For more flavour, you can even add some fresh pineapples and Chinese pickled sour plum (used in this steamed fish recipe). These ingredients help to enhance the taste of the golden syrup without intruding on the original flavour.
It is possible to buy golden syrup in your local supermarkets. If you are wondering, my baking instructor use to call this fake honey. So yes, you can simply use honey as a substitute.
Is lye water dangerous?
Sometimes called lime water or alkaline water, it is commonly used in making baked goods such as bagels, pretzels and noodles. It is used to increase the pH level of the dough besides giving it a nice shade of yellow. With noodles, lye water makes them springier for a better mouth feel.
According to this article from the government of South Australia, lye water is safe to use in small amount (spoonfuls) for cooking. Therefore, you can safely use it in this recipe.
Can lye water be substituted?
It depends. You may replace it with some baking soda. However, this will result in a slightly dry, crumbly and uneven coloured dough. If you are comfortable with the difference, then it is replaceable. Making your own lye water (by boiling baking soda) will also give the same result. I had tried and tested 6 times. Nothing beats the store bought lye water. The colour of the biscuits is much more even too.
Since golden syrup is acidic, some kind of alkaline is needed to neutralize it. Therefore, without lye water, the mooncake will be pale in colour and the texture will be hard. This theory is similar to the reaction of baking soda (alkaline) and vinegar (acid) which aids aeration in cakes helping to raise the dough. So, it is not possible to simply skip this ingredient.
Can all-purpose flour be used?
All-purpose flour will make the dough extremely hard due to the higher amount of gluten. It is best to use cake flour. Otherwise, you may try to substitute cake flour by combining 100g of all-purpose flour and 20g of cornstarch.
What if I don‘t have peanut oil?
Substitute it with any other colourless and flavourless oil such as corn oil or sunflower oil. Peanut oil is great for this recipe as it is much more fragrant compared to the other types of oil mentioned.
Getting the perfect shape from the mould
The special mould can be bought in speciality baking stores, selected Asian grocers or online. Common problem is the dough sticking to the mould causing the biscuits to look imperfect. Prevent this by dusting some flour into the mould.
Some moulds may have intricate designs especially on the sides. Ensure that the dough is fully pressed into the mould to get the full pattern.
Do not eat the mooncake biscuits immediately
After baking, these biscuits are rather hard and light in colour. Have some patience and let them sit for 2 to 3 days in an airtight container to allow the biscuits to soften. Most importantly, the signature shiny appearance of the mooncake biscuits appears when the oil from the paste seeps out to the skin.
Why do the biscuits crack during baking?
Doll biscuits may crack if you over baked the dough or if there is too little moisture in the dough. If you are making a large batch, it is advisable not to leave the unbaked biscuits openly. Cover the dough with a damp cloth to keep it moist before baking.