You won't find apple chunks inside these cinnamon-sugar dusted cake doughnuts from Flex Donuts, but you will find a puree of apples rolled into the dough. Most of it seamlessly melds into the dough but the occasional swirl stands out, a sweet and faintly spiced pure More

What adds to the anticipation of getting pastry chef Zac Young's Flex Donuts is watching him hold a large pastry bag and inject small, round doughnuts with filling. Young, who is executive pastry chef at Flex Mussels and a former contestant of Top Chef Just Desserts, is selling his doughnuts ($1.50) for two weeks in the takeout section of Zocalo in the Lowel Level Dining Concourse at Grand Central Terminal. Young offers five flavors: salted cajeta (caramelized goat's milk), tequila-lime, raspberry, spiced chocolate, and cinnamon sugar. More