How to properly terminate dish washer / garbage disposal?
I recently remodeled my kitchen, and the original wiring was just two romex's coming out of the wall and hardwired to the dishwasher and disposal respectively.   There are wiring enclosures on each appliance.  Evidently that was acceptable in times past.

I'm sure our more knowledgeable contributors will come by and cite the current code.

I decided to go with installing a wall box for each circuit, and installing a single 20A receptacle for each (assuming they are 20A 12g circuits).  This allows you to simply and definitively disconnect either when doing any servicing.  It's simple, safe, and straight forward.

You can get an appliance plug that wires into the disposal at the store.  My Bosch diswasher came with a power cord that terminated in a supplied plastic surface mount box.  I put that under the sink and connected an appliance rated cord and plug to it.