Cuckoo learnt to peck end off chocolate digestive (7)

'chocolate digestive' is the definition.
I can't tell whether this definition defines the answer.

'cuckoo learnt to peck end' is the wordplay.
'cuckoo' indicates an anagram (I've seen this in other clues).
'to' means one lot of letters go next to another (I've seen this in other clues).
'peck end' becomes 'e' (I can't explain this - if you can you should give a lot more credence to this answer).
'learnt' anagrammed gives 'nteral'.
'nteral' put after 'e' is 'ENTERAL'.

'off' acts as a link.

Can you help me to learn more?