The croissants and pastries at Morgan Larsson's Kiosk are so good this place should be located on the fabled sunken island of Atlantis. (Un)fortunately, it's right across the street from my office.
Every day the Kiosk has fresh handmade pastries for sale at very reasonable prices ($2-4). The quality of the ingredients - marzipan, whipped cream, fresh fruit, handmade vanilla custard - is like a sudden break with the perfunctory and prefab indulgences that characterise this neighbourhood.
The best croissants uptown of Ceci Cela. Perfect Danishes with fruit and almond paste. A shortbread heart unexpectedly filled with a melting rich vanilla custard. Swedish profiteroles filled with fresh raspberry puree and Bavarian cream. A liebeck (spelling?), puff pastry encasing almond paste and custard with a strawberry on top.
Illy coffee and espresso is served. Plentiful seating in the public atrium of the Sony building.
Sony building, 550 Madison (nearer the 55th street entrance)