First of recipes: one's extravagant duck dish (7)
I believe the answer is:
risotto
'dish' is the definition.
(risotto is a kind of dish)
'first of recipes one's extravagant duck' is the wordplay.
'first of' suggests taking the first letters.
'one's' becomes 'is' (roman numeral).
'extravagant' becomes 'ott' (I've seen this in other clues).
'duck' becomes 'o'.
The initial letter of 'recipes' is 'r'.
'r'+'is'+'ott'+'o'='RISOTTO'
(Other definitions for risotto that I've seen before include "Main course" , "Italian course" , "Italian recipe" , "Italian dish of rice, meat and vegetables" , "Perhaps Italian" .)