Prepared to cross Italy and Greece initially, but strayed (9)

'strayed' is the definition.
('digress' can be a synonym of 'stray')

'prepared to cross italy and greece initially' is the wordplay.
'prepared' becomes 'dressed' (definitely for salad).
'to cross' is an insertion indicator (some letters cross or go round others).
'italy' becomes 'i'.
'and' means one lot of letters go next to another.
'initially' indicates taking the first letters.
The initial letter of 'greece' is 'g'.
'i'+'g'='ig'
'dressed' placed around 'ig' is 'DIGRESSED'.

'but' acts as a link.