How to Make It
In a large saucepan, combine the sugar, Prosecco, water, vanilla bean and seeds, lemon zest, cinnamon stick half and cloves and bring to a boil. Add the pears and keep them submerged by covering them with a small lid. Reduce the heat to moderate and simmer until the pears are tender but not mushy, about 20 minutes. Using a slotted spoon, transfer the pears to a cutting board. Let cool, then thinly slice them lengthwise. Reserve the poaching liquid in the refrigerator for poaching other fruit.
In a bowl, using a fork, blend the ricotta with one of the egg yolks, and the salt and pepper. In another bowl, beat the remaining egg yolk with the milk.
On a well-floured work surface, roll out 1 disk of Crème Fraîche Pastry to a 13-inch round. Brush off any excess flour and transfer the round to a baking sheet lined with parchment paper.
Spread half of the ricotta mixture on the pastry, leaving a 2-inch border all around. Arrange half of the pear slices over the ricotta filling in a slightly overlapping circular pattern. Fold the edges of the pastry over the pears, crimping and pressing as you go; brush the pastry rim with half of the egg wash. Repeat with the remaining pastry, ricotta, pears and egg wash. Freeze the crostatas until firm, about 1 hour.
Preheat the oven to 375°. Bake the crostatas on the middle and lower racks of the oven for 40 minutes, or until deeply golden. Shift the baking sheets from top to bottom and front to back halfway through baking for even browning. Let cool. Drizzle with honey, cut into wedges and serve at room temperature.