แป้นทำขนมปลากริม (paen tham khanom pla krim) — a Wooden Board Bored All Over, with Two Ears to Rest It on a Pot: Press the Dough into Cold Water

"The dough is then pressed or forced through the pla krim board, so that the cooked dough drops into a bucket of cold water and becomes pla krim." (Sirindhorn Anthropology Centre, author พิชชา ทองขลิบ (Phitcha Thongkhlip), CC BY 4.0)

Cut a hardwood board round or polygonal, with an ear sticking out on each side, long enough to rest across the mouth of a pot or bucket.

Bore small round holes all over the board, evenly spaced.

Sand the holes and the wood smooth, with no splinters, and wash it clean.

Real photos of a แป้นทำขนมปลากริม (paen tham khanom pla krim) from พิพิธภัณฑ์พื้นบ้านจ่าทวี (Ja Thawee Folk Museum) (Sirindhorn Anthropology Centre, author พิชชา ทองขลิบ (Phitcha Thongkhlip), CC BY 4.0)

Boil or stir a batter of rice flour and arrowroot flour in a brass pan until it is thick enough. Rest the board across a bucket of cold water and press the dough through the holes; the strands drop into the cold water as pla krim, chewy, soft and smooth. Mind the hot dough.

Khanom pla krim is often eaten with khanom khai tao; in old times the pair was called khanom chaeng ma. Today a press of stainless steel or thick zinc sheet, made as two cans one inside the other, is used instead of the wooden board. Source: Sirindhorn Anthropology Centre, Traditional Objects of Everyday Use database, "แป้นทำขนมปลากริม" (CC BY 4.0 licence). **Limits** The source gives no size for the board or its holes.