Kitchen appliance is vital stuff, next to CPU (4,9)
I believe the answer is:
food processor
'kitchen appliance' is the definition.
(I've seen this before)
'vital stuff next to cpu' is the wordplay.
'vital stuff' becomes 'food' (I can't explain this - if you can you should believe this answer much more).
'next to' means one lot of letters go next to another.
'cpu' becomes 'processor' (synonyms).
'food'+'processor'='FOOD PROCESSOR'
'is' acts as a link.
Can you help me to learn more?
(Other definitions for food processor that I've seen before include "Kitchen appliance" , "Kitchen gadget" , "What is useful for chef" , "Blender or mixer" .)