Preheat 400 degrees F.
Chop the pecans to the consistency of rough crumbs. Toss with the butter, sugars and cinnamon in a small bowl. Spread the mixture out onto a baking sheet and cook in the oven 7 to 10 minutes, until darkened and lightly caramelized. Set aside to cool.
Roll out the puff pastry on a floured surface to 1/16-inch thickness. Cut the puff pastry sheet into 12 squares, approximately 3 by 3 inches. Lay out on a baking sheet and bake 15 to 20 minutes, until puffed and golden brown. Remove from the oven and set aside to cool.
Melt the butter with both the sugars in a skillet over medium heat. Add the pears. Cook until pears are just tender and juices thicken to a syrup consistency, about 6 to 8 minutes.
Whip the cream, granulated sugar and vanilla in a mixing bowl until it forms soft peaks.
Place a puff pastry square in the center of a serving bowl or plate. Top with a few pears, whipped cream and pecan pieces. Repeat this process 2 more times ending with a sprinkle of nuts.