Giuseppe's first story about old ice cream (6)
I believe the answer is:
gelato
'ice cream' is the definition.
(I've seen this before)
'giuseppe's first story about old' is the wordplay.
'giuseppe's first' becomes 'g' (1st letter of 'giuseppe').
'story' becomes 'tale' (synonyms).
'about' is a reversal indicator.
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'tale' in reverse letter order is 'elat'.
'g'+'elat'+'o'='GELATO'
(Other definitions for gelato that I've seen before include "Italian-style ice cream" , "Frozen food" , "treat in Milan?" , "Italian ice cream" .)