With a sharp kife, cut a slice into the rouded side of the chestnut. Do this for each chestnut.
Place chestnuts into instantpot.
Pour water over chestnuts, enough so that they're covered.
Turn on Instant Pot to low, 3 minutes. (*)
After cycle, do quick release immediately.
Leave chestnuts in the instapot, and let the water cool.
Once cooled and easy to handle, you can peel the chestnuts.
Store in an airtight jar in the fridge, for 2-3 days.
Notes
* If you like softer result, adjust pressure time to 4-5 min.We recommend to peal everything while it's still wet. It gets harder to peel once chestnuts are dry.