Old man's attempt to manipulate baker (10)

Here is my best explanation:

'baker' is the definition.
(thesaurus)

'old man's attempt to manipulate' is the wordplay.
'old man's' becomes 'pas' (both can mean father).
'attempt' becomes 'try' (synonyms).
'to manipulate' becomes 'cook' ('cook' can be a synonym of 'manipulate').
'pas'+'try'+'cook'='PASTRYCOOK'