YOU SAID:
What is your favorite food when you're at a party?
INTO JAPANESE
パーティーのときの好きな食べ物は何ですか?
BACK INTO ENGLISH
What is your favorite food to eat at parties?
INTO JAPANESE
パーティーで食べるのが好きな食べ物は何ですか?
BACK INTO ENGLISH
What is your favorite food to eat at parties?
That didn't even make that much sense in English.