Practised what a famous Norman did using gilt iron (6)

'practised' is the definition.
Although both the answer and definition are past participle verbs, I don't see how one could define the other.

'a famous norman did using gilt iron' is the wordplay.
I cannot really see how this works, but
'iron' could be 'fe' (chemical symbol for iron) and 'fe' is found within the answer.
'gilt' could be 'gold' (synonyms) and 'gold' is found within the remaining letters.
No letters remain.
This may be the basis of the clue (or it may be nonsense).

'what' is the link.

Can you help me to learn more?