Giada De Laurentiis -- The Best Fast Food Joint in America Is ...

Giada De Laurentiis dropped some incredibly useful news to our photog at LAX XMAS Eve -- the best fast food in America.

Our photog starts out slow, asking about naked cooking, but then he gets serious and asks her about the best fast food restaurant in America.

Giada thinks for a while but then delivers. Hint, the person who owns it is also famous, also a celebrity chef, also recently divorced.

Check out the joint. She seems to know where of she speaks.