Piece of wood - or a piece of cake? (6)
I believe the answer is:
batten
'piece of wood' is the definition.
(I've seen this before)
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for batten that I've seen before include "Fastener for tarpaulin" , "Gain nourishment" , "Piece of timber" , "Wooden fastening strip" , "Close securely, say the hatches" .)