Purple and White Mooncakes: A Twist on an Old Treat (With a Chocolate Variation)
Updated: Oct 2, 2020
Twenty years ago, I found myself in China during the Mid-Autumn Festival, living a stone's throw from the Forbidden Palace. The holiday was particularly memorable. Someone had gifted me a big box of assorted mooncakes, made in Taiwan. These pastries were different from the standard lotus root and bean paste varieties I grew up eating in my Cantonese family. The Taiwanese fillings were full of fruity, creamy flavors: matcha, taro, pineapple, candied melon. A veritable mooncake revelation!
The mooncake continues to be reimagined. In more recent years, the snowskin variety has supplanted the classic mooncake in many households. The reasons are not hard to guess: the newcomers are lighter and healthier. They are also a little chewy: think of a cross between the purple sweet potato balls and mochi. Plus they are easy to make and can be filled with virtually anything: custard, chocolate ganache, taro root, and even purple sweet potato puree. Readers already familiar with my blog will notice one ingredient that seems out of place in Chinese cuisine: milk.
Now that my daughter is old enough to appreciate the Chinese holidays, I have been experimenting with different recipes. Stay tuned for the results of my other experiments.
Filling (adapted from SideChef)
Purple sweet potato, 1 pound
Butter, ghee, or oil, 2 tablespoons
Glutinous rice flour, 1 tablespoon (optional)
Milk ¼ cup
Sugar, ¼ cup (or to taste)
Salt, a pinch
Mooncake “skin” (adapted from RedHouse Spice)
Glutinous rice flour, 9 tablespoons (I use Thai glutinous rice flour, which has a finer texture than Japanese mochiko, but the latter will work too)
Rice flour, 9 tablespoons
Powdered sugar, 9 tablespoons
Wheat starch (or cornstarch), 6 tablespoons
Milk, 1.5 cup
Vegetable oil, 3 tablespoons
Condensed milk, 3 tablespoons (optional, for richer flavor)
Potato starch, for dusting (or substitute cornstarch or toasted glutinous rice flour)
Steamer, Instant Pot, or microwave
food processor for sweet potato puree (unnecessary for other fillings)
Start by mixing the dry ingredients for the skin, then add the milk(s) and oil. Whisk to incorporate thoroughly. Some recipes insist on pouring the ingredients through a sieve. (I found it made no difference.)
Pour into a heat-proof container like a Pyrex measuring glass and steam the “skin” batter for 25 minutes.
The batter will solidify like mochi. Remove from the steamer as soon as it is safe to handle and place the dough on a clean (undusted) surface. Knead the dough for several minutes until it becomes a smooth and shiny ball. If you don’t have cooking gloves, use a plastic spatula to manipulate the skin.
Wrap tightly in saran wrap and chill in the refrigerator for at least half an hour. It is best to leave it for an hour or two, but do not go beyond 4 hours.
(Shortcut: if you don’t want to bother with steaming the dough, you can put the batter in the microwave with a lid. Heat on high for 1 minute, then remove from microwave and give it a good stir. Return to the microwave for another 30 seconds and stir. If the dough is set, you can remove it and then knead it. Otherwise, heat for another 10-15 seconds. The dough may be a little harder than what you get from putting it in the steamer, but it will be serviceable.
Wash, peel, and cut the sweet potatoes into cubes, and steam for 20 minutes.
After the sweet potatoes are soft enough to be mashed with a fork, put them in a food processor (this is necessary for creating a smooth paste without coarse fibers). Add all of the dry ingredients except for the rice flour. Then fold in the milk and fats.
At this point, you can decide to incorporate the rice flour to make the paste stiffer. If the paste is sufficiently solid, skip this step. If not, cook the paste. Using a non-stick pan on medium low, heat the paste and stir for about 10 minutes. The paste will thicken.
Refrigerate the paste until stiff (chilled overnight works fine). Scoop about 2 tablespoons of the paste and roll into small balls. Stop when you have rolled all of the balls and store in the refrigerator until ready to use.
Remove the “skin” from the refrigerator and divide into 21 -24 pieces. Roll the pieces into balls with the palm of your hands, and then flatten them gently into a round disc as if you were making dumpling skins. The discs should not be thin: you just want them big enough to cover the paste ball filling (see picture above).
Place one of the paste balls in the center of the skin, then bring the ends together, pinching to hide the purple centers. Roll in the palms of your hands and place the ball seam-side down. Dust the top with a little potato starch (or cornstarch). Insert the mooncake stamp in the press and dust with starch. Place the stamp over the ball and press down to stamp the ball, then release. Consume the mooncakes fresh.
For chocolate mooncakes:
Add 1/2 teaspoon of unsweetened cocoa powder to the "skin" batter.
Use cocoa powder instead of starch to dust the molds and mooncakes.
For the ganache filling:
Heavy whipping cream, 1 cup
Semi-sweet or bittersweet chocolate, 9-10 ounces, chopped into small pieces.
Butter, 2 tablespoons (optional)
1. Heat the cream over medium low until it simmers (do not allow the cream to boil, otherwise it will scorch the chocolate, creating a greasy mixture).
2. Add the cream to the butter and chocolate mixture.
3. Allow the ganache to stiffen at room temperature.