Here at Snack we love all things Français - particularly buttery pastry with frangipane like la galette des rois - literally the cake of kings - but actually the twelfth night or Epiphany cake. The galettes are eaten on January 6th and tradition dictates that a 'lucky bean' is baked into the cake, which can be an actual bean or something fancy like a figurine or small porcelain plates made for this purpose. The person who finds the bean is the king or queen for the evening and has the pleasure of wearing the gold paper crown the pâtisserie provides along with the cake.
Downtown pâtisserie Ceci Cela (one of my personal favorites and perhaps the bestest and cheapest - $1.50 - cafe au lait in the city) has them for $29, as a special order a day in advance.
I am certain there are many other shops around Gotham baking the kings cake for Sunday night, so I invite you to add them to this post via comments. Helpful details are the name of the shop, phone number or website, price of the cake and if it requires an advanced order. One listing per comment s'il vous plaît.