One part of it produces things like doughnuts (4)
I believe the answer is:
tori
'doughnuts' is the definition.
(I've seen this before)
'one part of it produces things' is the wordplay.
'one part' indicates an anagram (I've seen 'parts of' mean this).
'of' becomes 'o''.
'it' becomes ''t' (abbreviation. e.g. in 'tis).
'produces things' becomes 'ri' (I can't justify this - if you can you should give a lot more credence to this answer).
'o'+'t'='ot'
'ot' is an anagram of 'to'.
'to'+'ri'='TORI'
'like' acts as a link.
Can you help me to learn more?
(Other definitions for tori that I've seen before include "rings" , "Large mouldings on columns" , "doughnuts" .)