The name of Olivier Dessyn’s new pastry shop in Greenwich Village, Mille-feuille, is a term for what Americans call a napoleon. The ones he makes, with cream and praline fillings, are first-rate indulgences. So are his beautifully burnished croissants (modest in size but flaky and practically oozing butter), his pains au chocolat and his almond croissants. Another specialty of this French pastry chef are fine macarons in many flavors. And no wonder: he worked in Paris with the chef Pierre Hermé, who probably did more for the macaron than Proust did for the madeleine. Brownies (some with praline filling), cookies, madeleines and loaf cakes are also turned out by the busy bakers in the open kitchen. Soon, Mr. Dessyn promises summer fruit tartlets, éclairs and other classics, as well as some sandwiches and salads to enjoy at the cafe tables that are coming for sidewalk snacks.