How to Make It
In a large saucepan, combine 1 1/2 cups of the sugar with the vanilla bean and seeds and the water. Cook over high heat, stirring, until the sugar dissolves, about 8 minutes. Add the quince wedges and bring just to a boil. Reduce the heat to low, cover and simmer until tender, about 2 hours; occasionally submerge the quinces in the poaching liquid. Let the quinces cool in the liquid.
Preheat the oven to 375°. Melt the butter in a medium skillet. Sprinkle the remaining 1 1/3 cups of sugar over the butter and cook over moderate heat, without stirring, until the sugar just begins to brown around the edges, about 2 minutes. Cook, stirring gently, until the caramel turns dark golden, 6 to 8 minutes. Immediately pour the caramel into eight 4-inch-wide ramekins (1 1/3 -cup capacity). Swirl the caramel in the ramekins to coat the bottoms.
Drain the quinces and arrange the wedges in the ramekins in overlapping circles; scatter the raisins on top.
On a lightly floured surface, roll out the puff pastry 1/8 inch thick. using a large biscuit cutter or small bowl, cut eight 4-inch rounds from the pastry; make two 1-inch slits in the center of each. Top the quinces with the dough rounds and bake for about 45 minutes, or until the crust is golden and the juices are bubbling. Let cool slightly, then invert onto plates. Serve with Sheep's Milk Ice Cream.