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"How Can I Get My Dumplings Extra Crispy?"
I just got back from Taiwan where I think I ate at Ding Tai Fung three or four times. Their guo tie are amazing and they have this crispy film along the bottom that connects them any idea how they do that?
—Sent by anniehsing
Guo tie, also known as potstickers, Peking ravioli, or gyoza (in Japanese) are fried Chinese jiaozi—meat or vegetable-stuffed dumplings made with a wheat-based wrapper. They can be steamed or boiled (in which case they'd be called zhengjiao or shuijao*), if all you're after is tender skins around a tasty filling, but in my opinion, there's no better way to cook them than to pan fry them, the goal being to maximize the textural difference between the tender, steamed tops, and the golden brown, crisp, bottoms.
*Check out The Serious Eats Guide To Dumpling Styles Around the World for more details!
The absolute easiest and most foolproof way to do this is to divide the cooking process into two phases, starting by steaming or boiling them until the skins and fillings are completely cooked through, then draining them, letting the excess moisture dry off, and pan-frying them in a hot wok or skillet in a shallow pool of oil. What you end up with are these:
Notice how cleanly delineated the line of crispy-fried-bottom is compared to the tender-steamy-top? That's the hallmark of a boiled-then-fried guo tie.
(You can get the full recipe here)
But what if you're more interested in something like this?
Not only are the bottoms of the dumplings crispy, but they actually have a layer of lacy, crispy browned bits that extend well-beyond the edges of the wrappers. Sort of like the dumpling equivalent of a Shady Glen cheeseburger. How the heck do they do that?
Well it starts with a hybrid frying-steaming technique. Raw dumplings are placed in a skillet with hot oil until their bottoms are browned. Once they're nice and crisp, water is added, and the pot is immediately covered. As the water steams away, it cooks the tops of the dumplings, getting them soft and pliant. Eventually, once all the water has evaporated, the dumplings begin to fry once again, re-crisping their bottoms. The result is a tender-topped crisp-bottomed dumpling all made in a single pan.
But what do you need to form that extra skin? The answer is starch. Raw dumplings&mdaswhether hand-made with homemade wrapper dough or with store-bought pre-rolled skins—have some degree of starch on their exterior to prevent them or the raw skins from sticking together. This starch can come in the form of cornstarch (for most packaged dumpling wrappers) or flour (for home-made dumplings). As the dumplings steams inside the skillet, the starch will end up dissolving in the water and dripping down to the bottom of the pan.
If enough starch makes it to the bottom of the pan, as the water continues to evaporate, you eventually end up with a very concentrated starch slurry that forms a thin, thin coating on the bottom of the skillet. This slurry will brown and crisp—just like a pancake or a crêpe. The more starch you had to begin with, the thicker this crepe-like finish will be.
In extreme cases, like the dumplings pictured above from the Din Tai Fung world-wide restaurant chain, the starch can form a completely solid layer, connecting all the dumplings into a single sheet, like pills in a blister pack. The world's most delicious blister pack that is.
If you want to get similar results at home, there are only two tricks you really need. First is to add a bit of extra starch to your dumplings. Dust them with cornstarch, shaking off the excess before the initial fry. Second is to use a non-stick skillet, or an extremely well-seasoned cast iron pan. You'll be turning out dumpling blister packs in no time.
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About the author: J. Kenji Lopez-Alt is the Chief Creative Officer of Serious Eats where he likes to explore the science of home cooking in his weekly column The Food Lab. You can follow him at @thefoodlab on Twitter, or at The Food Lab on Facebook.