KO EN Japanese Dessert⏱ 30 minEdit history

Kuzukiri (Kudzu Starch Noodles in Black Sugar Syrup)

Name: Kuzukiri (Kudzu Starch Noodles in Black Sugar Syrup)
Prep time: 15 min
Cook time: 15 min
Total time: 30 min
Yield: 2 servings
Cuisine: Japanese
Ingredients: 50 g kudzu starch (hon-kuzu); 150 ml water; 80 g dark muscovado or Okinawan kokuto; 80 ml water; 1 shallow flat metal tray; 1 bowl of iced water

Kyoto's summer dessert: kudzu starch stirred into water, poured thin into a flat tray, set over boiling water, cooled in ice water, cut into noodles and dipped in black sugar syrup. Gelatine and agar set as they cool; kudzu starch sets while it is heated. So each sheet is set over the heat, moved straight into ice water, and eaten where it was made.

Ingredients

2servings

kudzu starch (hon-kuzu) · potato starch if you cannot get it50 g
water150 ml
Black sugar syrup
dark muscovado or Okinawan kokuto80 g
water80 ml
Equipment
shallow flat metal tray · 15-20cm, with a low rim1
bowl of iced water1

Steps

Melt the sugar in the water over a low heat, simmer 3 minutes and leave it to cool.
⏲ 3 min
Add the water to the kudzu starch a little at a time, rubbing out the lumps with your fingers, and sieve it once. The starch settles fast, so stir it every time before you pour.
Bring a wide pan of water to the boil and turn it down to medium. Float the tray on the water, pour in starch liquid 2mm deep and tilt the tray to spread it evenly.
Leave it floating 1 minute and the surface sets white. Then sink the tray into the boiling water for another minute. It is done when the white is gone and it is completely clear.
⏲ 2 min
Move the tray straight into the iced water to cool. Lift an edge with a fingertip and peel the sheet off in one piece.
⏲ 30 sec
Take it from the ice water to a board and cut it into long strips 7-8mm wide. Repeat with the rest of the starch.
Float the noodles in a bowl of iced water and serve at once with the syrup. Dip each strand in the syrup to eat.

Tips & Variations

Variations

With potato starch: Korean Wikipedia notes that because kudzu is expensive, versions made with potato starch are widely used in its place. The method does not change.
Dried kuzukiri: the article notes it is also dried and added to nabe, Japanese hot pots.
With honey: the article also describes it eaten with chilled honey poured over.
Kyoto's other clear noodle: tokoroten is agar set in a mould and pushed out into strands. They look alike, but tokoroten sets as it cools and kuzukiri sets over boiling water.

Tips

It sets as it cooks, not as it cools. Korean Wikipedia gives the difference: gelatine and agar set as they cool after heating, but kuzukiri, being a starch, sets while it is heated. Panna cotta's gelatine and yokan's agar are poured into a mould and waited for — "It sets at around 40C and does not melt until past 85C". Even dotori-muk's starch is "Acorn starch whisked into water, boiled and left to set." Kuzukiri does not wait: each thin sheet is set over the heat and moved straight into ice water.
So each sheet is thin. Because it has to set while heating, it is poured 2mm deep so the heat reaches all of it quickly. Pour several thin sheets rather than one thick one.
The colour tells you when. The surface turning white is only halfway. Sunk and turned clear all the way through, it is cooked through.
Eat it where it was made. Dotori-muk's warning about the fridge applies: in the cold "the starch network rearranges more coarsely, and water is pushed out of it." Kuzukiri is served floating in iced water, so it cannot wait. Make only what you will eat.
The starch settles. Left standing, the starch sinks to the bottom of the water. Stir before every pour or the sheets come out uneven.