Step 1: Steam the salted egg yolk and let it cool.

Step 2: Crush the salted egg yolk with a spoon. It doesn’t matter if it’s a little grainy, it will taste better.

Step 3: Peel 110 grams of mung beans.

Step 4: Rinse the peeled mung beans with clean water, drain the water, put them in a bowl, add 200 grams of water and steam them in a steamer for 40 minutes.

Step 5: After steaming, crush the mung beans into powder.

Step 6: Prepare 30 grams of lard. If you don't like it, you can use "butter" instead, but you need to reduce the amount.

Step 7: While hot, add 110 grams of sugar, 30 grams of lard and 3 crushed salted egg yolks to the steamed mung beans.

Step 8: Stir evenly to prepare the egg yolk filling.

Step 9: The filling is a little watery at this time, and it will be easier to use if you put it in the refrigerator.

Step 10: Prepare the dough and fillings. To make the dough, put the yeast into warm water and dissolve it. After soaking for 5 minutes, stir it evenly with chopsticks. Put the flour in a bowl and add sugar. After mixing evenly, pour the yeast water and pour it little by little until the dough is completely formed. Then cover and let rest for 10 minutes to relax the gluten. Take the dough out and knead it repeatedly until it is smooth. After kneading is smooth, put it in a larger basin, cover it with a lid, and place it in a constant temperature place, preferably around 30 degrees, to ferment naturally until the dough doubles in size. After fermentation, take it out and place it on the chopping board. Knead the air until smooth.

Step 11: Roll out the risen dough into a rectangular sheet 36 cm long and 28 cm wide.

Step 12: Sprinkle some dry flour to prevent sticking.

Step 13: After rolling out, use a rolling pin to push back the edge of the dough and the edges will be very straight, which is easier to operate.

Step 14: After rolling out, cover with plastic wrap and let sit for 5 minutes to let the dough relax.

Step 15: Cut the dough vertically downward at the center point.

Step 16: Evenly spread all the egg yolk filling. Pay attention to leaving about 1 cm of dough on the edge, do not apply fillings, and use it as a binding dough.

Step 17: Turn the lower right corner of the dough up and cover the upper right corner of the dough. Press down the edges to avoid leaking the filling.

Step 18: Fold the dough to cover the upper left corner again, and press the edges similarly.

Step 19: Turn the lower left corner of the dough upward.

Step 20: After flipping, pinch the interface tightly. Become the egg yolk layer cake green body.

Step 21: Use your hands to seal the seams on the edges again, otherwise they will open during steaming.

Step 22: Put oil paper underneath, put it in the steamer, don't turn on the heat, and cover it. Continue to rise for about 30 minutes.

Step 23: After the second batch of egg yolk layer cake is completed, turn on the heat, boil the water and steam for about 25 minutes.

Step 24: After steaming, you can insert a toothpick into the cake body. If the toothpick comes out dry and does not bring out any sticky dough, it means it has been steamed.

Step 25: Let cool and cut into pieces. You can eat it hot or cold.