Cantonese Mooncake with Salted Egg Yolk (广式月饼)

The cooking procedure

Before we go into the detailed tips & tricks, let me first summarise the process to give you a clear idea of the cooking steps:

1. Prepare the filling: Use dried lotus seeds to make lotus paste. If using raw salted eggs, boil them or bake the yolks in the oven.
2. Make the dough: Mix syrup, lye water, oil & flour to make a dough.
3. Assemble & shape: Wrap salted egg yolk with lotus paste, then use a piece of dough to wrap the filling. Place it into a mooncake mould to shape.
4. Bake: Cook the cakes in the oven. Brush egg wash twice during the process.
5. Rest: Store cooled cakes in a container and rest for 1-2 days until they become soft and shinny.

How to make lotus seed paste

Homemade lotus seed paste has two great advantages: There is no additives/preservatives; You can adjust its sweetness to your liking. It‘s not difficult to make. All you need is some time and a little patience. Here are a few tips:

• Soak dried lotus seeds long enough (overnight preferably) to reduce the boiling time. 
• Drain cooked seeds before you put them into a food processor. This will shorten the frying process later on. If you find it difficult to blend, add a little water to help.
• When frying, you need to constantly stir/flip the paste otherwise you might end up with a burnt taste. Non-stick pan helps a lot for the process.
• The finished paste should be quite dry and easily foldable into a solid block. Wet paste would make assembly very challenging. It also causes excess steam during baking thus affecting the look of the mooncakes.

Use salted egg yolks in the filling

It’s not unusual to find classic Chinese dishes wonderfully combining the taste of sweetness and saltiness. Cantonese mooncake filled with sweet paste and salted egg yolk are a great example. Aromatic, savoury in taste, powdery in texture, salted egg yolks bring Cantonese style mooncakes to another level.

I usually make small-sized mooncakes (about 50 grams each) which hold one whole egg yolk inside. You may use half of a yolk and a little more lotus seed paste if prefer. If your mooncake mould makes the traditional size (100g each), you can place two yolks to make it extra “luxurious”. 

How to prepare the yolks

You may purchase ready-to-use salted egg yolks which often come in airtight plastic bags. Alternatively you can use raw salted duck eggs and cook the yolks yourself. Here are two methods:

• Boiling method: Start cooking the eggs in cold water. Once the water begins to boil, turn the heat down and simmer for 6 minutes. Rinse under cold water then peel off the shell and egg white as soon as cool enough to touch.
• Baking method: Crack the shell of a raw salted egg. Remove the hardened yolk. Wash off the membrane around it. Place on a baking tray then spray with Baijiu (a type of strong Chinese liquor). Bake in the oven preheated to 190°C / 375°F until you see a ring of bubbles appear around the bottom of the yolks (it takes about 8 minutes).

What is Lye water

Essential to Cantonese mooncake, lye water (aka Kansui) is a food grade potassium carbonate solution used to raise the PH of the dough (neutralize the acid in the syrup). Moreover, it helps the dough to gain an appetizing brown colour after baking and a fluffy, tender texture. However, please follow the recipe and do not increase its volume as this will result in a bitter taste.

If you don’t have access to shop-bought lye water, check out my post on Lye Water and Its Homemade Substitute to learn how to make your own using two basic ingredients: baking soda and water.

Use invert syrup or golden syrup

Traditional Cantonese mooncake recipe calls for a particular sugary ingredients for the dough: invert syrup (inverted sugar syrup/转化糖浆).

“Invert syrup is an edible mixture of two simple sugars—glucose and fructose—that is made by heating sucrose (table sugar) with water. It is thought to be sweeter than table sugar, and foods that contain it retain moisture and crystallize less easily.”     —Wikipedia

Through recipe testing, I found out that shop bought golden syrup works for my recipe too. The dough tends to be a little stickier than the one made with invert syrup. So you may need to dust a little extra cornstarch when handling the dough and moulding the mooncakes.

Some people use honey as substitute. It works, but the dough tears very easily making assembly quite challenging.

The ideal dough filling ratio

Once you have all the parts (lotus seed paste, egg yolks, dough) ready, you will need to use a scale to measure for each cake. The dough filling ratio varies depending on personal preferences. It can be 2:8, 3:7 or 4:6. I always enjoy the taste of the dough so my recipe goes for 4:6 ratio. That means for a 50g mooncake, the dough weighs 20g and the total weight of lotus seed paste & egg yolk should be 30g.

Please feel free to adjust the ratio. However, if you are new to making mooncakes, I suggest you start with the 4:6 ratio as it’s easier to assemble with a little extra dough.

Check out my video instruction (in the recipe card below) to see how I wrap the egg yolk with lotus seed paste first, then wrap the filling with the dough to finish.

Where to find mooncake moulds

These are the mooncake moulds that I purchased in China. You can find them on mainstream online shopping platforms such as eBay, Amazon, etc. and in some Chinese/Asian stores.

These modern moulds usually come with several plates in different designs. They are very easy to use, making moulding a quick & neat job (Please refer to my video in the recipe card below).

How to bake them to perfection

It takes three steps to bake mooncakes:

1. Bake at 190°C / 375°F for 5 minutes to harden the delicate top of the mooncakes. This will make egg wash brushing easy.
2. Reduce the heat to 160°C / 320°F then bake for a further 5 minutes. Brush another layer of egg wash on top.
3. Put the mooncakes back to the oven. The last baking process takes another 10-15 minutes. I suggest you check at 10 minutes. They are done once evenly brown.

Rest the mooncakes before eating

Freshly baked mooncakes are quite dry to touch. Once completely cooled, you are advised to store them in an airtight container for at least 1-2 days before consuming. During the resting period, mooncakes become softer and gain a nice shiny apperance. Chineses call this process Hui you/回油, meaning “the return of oil”.

You may keep the mooncakes in the fridge for up to 2 weeks. Bright back to room temperature prior to serving.

No bake mooncake with custard filling

If you don’t fancy baking, check out my recipe for Snow Skin Mooncake with Custard Filling. There isn’t baking involved and you can make them in beautiful colours using natural ingredients.

A piece of homemade mooncake to eat, a cup of Chinese tea to drink, a beautiful full moon to admire and some moon related fairytales to share with my children, for me, this would be a perfect Mid-Autumn Festival as I live far away from my family in China.

I hope this detailed post has inspired you to make some mooncakes for your loved ones for this special occasion. Wish you all a very happy “Mooncake Day”!