Enjoy the Mid-Autumn Festival with modern Lava Custard Mooncakes: a crisp, buttery cookie-like shell, a smooth sweet custard layer, and a molten salted egg yolk center that oozes when you cut into it.
The Mid-Autumn Festival is coming—why not make these show-stopping Lava Custard Mooncakes this year?
About Mid-Autumn Festival
Also called the Moon Festival or Mooncake Festival, the Mid-Autumn Festival is a long-standing Chinese celebration held on the 15th day of the 8th month of the lunisolar calendar. Traditionally it marks harvest time and the night when the moon is brightest and fullest. Sharing mooncakes is a central custom: the round shape symbolizes completeness and family reunion.
What Are Lava Custard Mooncakes?
Lava Custard Mooncakes are a contemporary take on classic mooncakes. From the outside they resemble traditional mooncakes, but the ingredients and textures differ significantly. These feature three distinct layers: a tender, crumbly, cookie-like exterior; a silky sweet custard middle; and a molten salted egg yolk core that creates the signature lava effect when sliced.
These mooncakes require time and care, but the payoff — slicing open a warm pastry to reveal the flowing salted yolk — is worth it. They’re a crowd-pleaser, even for people who don’t usually like traditional mooncakes. Bake several batches to enjoy fresh and keep extras frozen for gifting or later baking.
Special Ingredients
- Salted egg yolks. Typically from salted duck eggs cured by brining or coating in a salt-clay mix. Use whole yolks that are orange-red and firm once cooked.
- Custard powder. A powdered mix that yields a stable, flavorful custard with less risk of curdling than egg-only custards.
- Milk powder. Adds richness and depth to the custard.
- Evaporated milk. Concentrated milk that produces a creamier, richer texture in fillings and dough.
- Condensed milk. Sweetens and enriches the custard filling.
Preparing Salted Egg Yolks
You can buy vacuum-packed yolks, but whole salted duck eggs usually taste better. If your eggs are encased in clay, wash them first. Crack the eggs, separate yolks, and clean off the white membranes under running water. If any yolk smells off or looks discolored, discard it. Lightly spray cooked yolks with a tiny amount of Shaoxing wine, baijiu, or vodka to reduce fishiness.
Cook the yolks before using them. For small batches, steam; for larger batches, bake.
- Steaming: Steam yolks in a heatproof dish over boiling water for 8–9 minutes on medium heat.
- Baking: Arrange yolks on a foil-lined tray and bake at 320°F (160°C) for about 10 minutes.
Equipment
- Kitchen scale. Weighing ingredients gives the most consistent results.
- Pastry brush. A soft-bristle brush helps apply a light, even egg wash without blurring patterns.
- Mooncake mold. A 50 g mold is recommended for these recipes; a 65 g mold can work if you adjust portions.
- Small spray bottle. Misting mooncakes before baking helps prevent cracking.
Mold Size and Why It Matters
Use a standard 50 g mooncake mold for best results; a larger mold increases the risk of cracking because the lava filling can destabilize the pastry during baking.
Make These Mooncakes in Advance
This recipe benefits from being spread over three days for easier workflow and better results:
- Day 1: Prepare the lava and custard fillings (lava needs time to set in the freezer).
- Day 2: Make the skin dough and assemble mooncakes; freeze assembled mooncakes for at least 4 hours.
- Day 3: Bake and finish the mooncakes.
Pro Tips
- Make larger batches. Since these take time, prepare extra for gifting or future baking.
- Work fillings in small sets. Take out only a few lava cores at a time to prevent melting.
- Move quickly when assembling. Cold fillings and dough are easier to handle and reduce tearing.
- Rest the dough. Refrigerate wrapped dough for an hour to relax gluten and make wrapping easier.
- Flour the mold lightly. Dust the mold and dough to prevent sticking, then shake off excess flour.
- Apply egg wash sparingly. Use a soft-bristle brush and remove excess from the brush to keep patterns sharp.
- Avoid overbaking. Excess heat can cause cracking and collapse; bake until just golden.
Storage
Cool mooncakes completely before storing in an airtight container. They keep 3 days at room temperature or up to a week refrigerated. The exterior is crispiest fresh from the oven and will soften over time; reheat briefly for the best molten center. For long-term storage, freeze unbaked assembled mooncakes and bake as needed—frozen unbaked mooncakes can last several months.
Related Recipes
- Honey Pistachio Mooncakes
- Cookie Crust Mooncakes
- Thousand Layers Lava Custard Mooncakes
Lava Custard Mooncakes
Ingredients
Lava Filling
- 3 salted egg yolks (45 g)
- 50 g heavy whipping cream
- 20 g salted butter, room temperature
- 20 g granulated sugar
- 10 g evaporated milk
- 10 g milk powder
Custard Filling
- 2 salted egg yolks (30 g)
- 1 egg
- 75 g evaporated milk
- 40 g milk
- 40 g granulated sugar
- 30 g milk powder
- 25 g custard powder
- 25 g salted butter, room temperature
- 12 g condensed milk
- 12 g cake flour
Mooncake Skin
- 70 g salted butter, room temperature
- 35 g confectioners’ sugar
- 12 g egg yolk
- 13 g evaporated milk
- 130 g cake flour
- 12 g custard powder
Egg Wash
- 1 egg yolk
- 1 tbsp water
Instructions
Overview (3 days recommended)
- Day 1: Make the lava and custard fillings.
- Day 2: Make the skin and assemble mooncakes, then freeze.
- Day 3: Bake and finish the mooncakes.
Prepare Salted Egg Yolks
- Crack open salted duck eggs, separate yolks, and clean them. Place yolks in a heatproof dish.
- Lightly spray with a small amount of alcohol (Shaoxing wine, baijiu, or vodka) to reduce fishiness.
- Steam yolks for 8–9 minutes on medium heat, or bake at 320°F (160°C) for about 10 minutes if making many.
Lava Filling
- Blend 3 steamed yolks with the listed lava ingredients until smooth.
- Gently heat in a non-stick pan on low until warm and sugar dissolves—do not boil.
- Pour into a small freezer-safe container lined with cling wrap and freeze 2–3 hours until firm.
- Cut or portion into 15 equal pieces (9–10 g each), shape into balls, and refreeze at least 4 hours or overnight.
Custard Filling
- Blend 2 steamed yolks with custard ingredients until smooth.
- Heat the mixture on low in a non-stick pan, stirring constantly until it thickens into a soft dough—avoid overcooking.
- Cover with cling wrap while hot to prevent drying. Cool to room temperature, then refrigerate until needed.
Mooncake Skin
- Cream salted butter with sifted confectioners’ sugar until combined.
- Add egg yolk and evaporated milk; mix until smooth.
- Sift in cake flour and custard powder; combine to form a dough.
- Wrap and refrigerate the dough for 1 hour.
Assemble Mooncakes
- Divide the custard filling into 15 equal pieces (21–22 g) and shape into balls.
- Create a deep well in each custard ball, insert one frozen lava ball, then seal and reshape. Work quickly to prevent melting.
- Portion skin dough into 15 pieces (18–19 g). Flatten each piece, place a filled custard ball in the center, stretch the dough over it, and seal.
- Lightly dust the mold and dough with flour, press firmly into a 50 g mold, then release the shaped mooncake. Repeat for all pieces.
- Place assembled mooncakes on a tray, cover, and freeze for at least 4 hours or overnight before baking.
Bake Mooncakes
- Preheat oven to 425°F (220°C). Line a baking sheet with parchment.
- Place frozen mooncakes on the sheet and mist lightly with water to prevent cracking.
- Bake 5 minutes, remove and cool on the pan for 10 minutes.
- Prepare egg wash by mixing egg yolk with water. Use a soft pastry brush to apply a thin coat to each mooncake.
- Return to the oven and bake another 8–10 minutes until golden. Avoid overbaking to prevent cracking.
- Serve warm for the best molten lava effect; reheat in oven or microwave to revive the runny center if needed.