Di Gua Qiu
地瓜球·(dìguā qiú)
Ye Shi (夜市) – Recreating the Night Market
Standing in a humid Taipei night market, watching a vendor rhythmically smash golden dough in a giant wok until it inflates like magic, the neon buzzing, a wire spider plunging into 350°F oil, is an unforgettable education in street food. The secret to these hollow spheres isn't a complex trick—it's cheap tapioca starch and the physical act of violently pressing the dough while it fries. Abandoning flawed internet hacks, translating the vendor's technique into exact measurements ensures the tapioca dough puffs into crisp shells. Pull them from the oil, shake off the grease, and eat them standing up.
Before you start
Set the sweet potato cubes in a steamer basket over simmering water and steam until completely tender.
This should take about 15 to 20 minutes. Dry steaming concentrates their natural sweetness and controls the moisture; boiling them will waterlog the dough.
Transfer the steaming hot cubes to a bowl, immediately add the sugar, and mash into a smooth paste.
It is critical to do this while the potatoes are piping hot so the thermal heat melts the sugar into a natural syrup.
Fold the tapioca starch into the hot mash, then use your hands to knead it until it feels like soft dough.
If the dough is cracking, add warm water exactly one teaspoon at a time. If it is sticking aggressively to your fingers, dust in a little more tapioca starch.
Pinch off portions of the dough and roll them into 1-inch balls.
Keep them small, as they will expand significantly. Cover the finished balls with a damp paper towel so they do not dry out before frying.
Ingredients
- Japanese sweet potato250 g
- tapioca starch1 cup
- granulated white sugar3 tbsp
- neutral cooking oil1 qt
- warm water1 tbsp
Method
- 01
Heat two inches of neutral oil in a heavy pot to 250°F and fry a batch of balls untouched for two to three minutes.
Do not crowd the pot. Let them fry gently until a slightly hard crust forms and they naturally float to the surface.
- 02
Using a metal slotted spoon, firmly press the floating balls down against the bottom or sides of the pot to squeeze out the air.
Release the pressure and watch them inflate. Repeat this motion 10 to 15 times per ball; the expanding internal steam creates the signature hollow center. If you press them before the crust sets, they will simply flatten and break.
- 03
Once the balls are large, hollow, and pale gold, crank the heat to high to reach 350°F and fry vigorously for a final 45 seconds.
This flash-crisping technique forces out residual oil and locks in a rigid outer shell so they do not collapse into sad, wrinkled discs when cooling.
- 04
Remove the finished balls with a spider and let them drain on paper towels.
They are best eaten within fifteen minutes while the contrast between the shattering crust and chewy, hollow interior is at its absolute peak.
Notes
If using standard American orange sweet potatoes, be prepared to add an extra two to four tablespoons of tapioca starch.
American varieties contain significantly more moisture than Asian varieties. Microwaving or baking them instead of steaming can also help drive off excess water.
The rolled, raw dough balls can be frozen on a baking sheet and stored in a ziplock bag for later.
Fry them directly from frozen on a weeknight; they will just require an extra minute or two in the initial low-temp fry to thaw and set their crust.