I don’t braise my bok choy but whether its fiberous depends on how big the bok choy is. The bok choy sold in western markets are usually big and fiberous to my taste. Even the baby bok choy are usually a little old. Check out your Asian grocer around to see if they are any better.
Too old:
The top two below are more tender:
Bok choy rabe- heavenly.
Hence, try getting the smallest size you can find.
