Outlaw, commanding officer held, is bit of a pig (5)
I believe the answer is:
bacon
'bit of a pig' is the definition.
'bacon' can be an answer for 'pig' (I've seen this before). I'm not certain of the 'bit of a' bit.
'outlaw commanding officer held' is the wordplay.
'outlaw' becomes 'ban' (banning is a kind of outlawing).
'commanding officer' becomes 'co'.
'held' indicates putting letters inside.
'ban' placed around 'co' is 'BACON'.
'is' is the link.
Can you help me to learn more?
(Other definitions for bacon that I've seen before include "Old scientist" , "Cured back or side of pork" , "rasher" , "Pig meat N essayist" , "What the breadwinner brings home?" .)