Mama's Fish House, Maui
If there was only one restaurant where you could eat in Maui: Mama's Fish House is it. Let's just say that it is famous for a reason.
Serving traditional Hawaiian cuisine, the restaurant has a 100% beach-y atmosphere and food, which is beyond delicious. There is literally nothing on the menu that you shouldn't order. You can't go wrong.
(It is a bit pricy - but 100% worth the one time splurge.)