If you have never been to the Neue Gallery, take a walk around and look at the art and amazingly beautiful architecture of the building.
Whether you go to look at the art or not, the Cafe Sabarsky on the first floor is a fantastic place to have lunch, or coffee and dessert. The breakfast looks amazing, but you must arrive before 11am! I recommend the superb beef goulash with spatzle. Choose a strong coffee, or esspresso with whipped cream, interesting pots of tea, or syrup flavored waters from the drink menu.
85th St @ 5th Ave