3yolks of hard-boiled eggs, or cooked salted duck egg yolkssee note 1
50gunsalted butter, softened
30gsugaror 40g if using salted egg yolks
30gfull-fat milk powdersee note 2 for substitutes
For the dough
175gbao flour/cake flour, or all-purpose floursee note 3
1teaspooninstant dry yeastsee note 4
1teaspoonbaking powder
1tablespoonsugar
1tablespoonneutral cooking oil
90glukewarm watersee note 5
Instructions
Prepare the filling
Use the back of a spoon to mash the yolks to a fine texture (It’s easier to do while the yolks are warm).
Add sugar, butter and milk powder. Mix very well until a smooth paste forms. Put into the fridge to harden a little.
Make the dough
IF USING HANDS: Mix flour, yeast, baking powder, sugar and oil in a bowl. Add water gradually while mixing with chopsticks/spatula. Combine with your hands to form a rough-looking dough. Rest (covered) for 10 mins then knead again until very smooth.
IF USING A STAND MIXER:Add all the ingredients for the dough into the mixing bowl. Knead on low speed for about 8 mins until a smooth dough forms.
Roll the wrappers
Divide the dough into 8 equal parts. Work on one piece at a time and make sure you cover the rest to prevent it from drying out.
With a rolling pin, flatten one piece into a disc-like wrapper, about 9cm in diameter. Ideally, it should be thinner on the edge and thicker in the middle (See the rolling technique in the video above).
Shape the buns
Place a spoonful of the filling in the middle of a wrapper. Seal the bun completely using whatever method that you feel most comfortable with. Repeat to assemble all the buns.
Rest the buns
With the sealed side facing down, place the buns into a steamer basket lined with parchment paper (or in cupcake paper moulds as shown in the post above). Alternatively, brush a thin layer of oil if using a metal/plastic steamer.
Leave to rest for about 30 minutes until they become very light & plump (They will become a little bigger but not double in size).
Steam the buns
Bring water to a full boil in a wok/pot. Put in the steamer basket. Cook over medium-high heat for 8 mins. Serve warm.
Store & reheat
It’s not recommended to store uncooked buns. However, cooked buns freeze very well. Consume within three months.
To reheat: Defrost in the fridge then steam for 3 mins. Alternatively, steam for 6 mins without defrosting.
Notes
1. There are two ways to cook raw salted duck egg yolks:
Option 1: Cook them in the shell in boiling water for 8 minutes. Peel off the shell and the egg whites.
Option 2: Crack the eggs and rinse off the egg whites. Steam the yolks for 8 minutes or bake them in a preheated oven at 190°C / 375°F for 8 minutes.
2. You may replace milk powder with the traditional style custard powder which contains egg and milk. Bird’s custard powder (a popular brand) is not an ideal substitute as it’s made of cornstarch and flavourings. But it would be OK if you’d like your buns dairy-free.3. To imitate the restaurant style custard buns, it’s best to use low gluten flour, such as special bao flour (available in Chinese stores) or cake flour which has 7-8g protein per 100g flour. If unavailable, you may use all-purpose flour which has 10-11g protein per 100g flour.4. Instant dry yeast can be mixed directly with flour. If using active dry yeast which has larger granules, dissolve it in water first then mix with other ingredients.5. The flour-water ratio may vary slightly depending on the type and brand of your flour. Please feel free to adjust. The dough should be soft but not sticky.