potato flour

How to freeze powder?

Add 2.5 parts of water to 1 part of potato flour, mix well, take a small pot, add 2 parts of water to the pot to boil, turn down the heat, slowly pour the prepared potato flour water into the pot, stir while pouring, stir until it turns black and transparent with bubbles, and then turn off the heat.

Pour the potato powder into the box, flatten it and put it in the refrigerator to cool.

It's set when it's completely cold. Add water directly to the box and cut it into small pieces. If you take it out and cut it, the knife won't stick well. Is it cold or fried?