Heat oven to 400°F. Line 2 cookie sheets with cooking parchment paper. On work surface sprinkled with 3 tablespoons flour, roll puff pastry to 1/8-inch thickness. Cut into 6 (4-inch) rounds. Cut additional shapes, such as leaves or stars, from scraps. Place rounds on 1 cookie sheet and shapes on second cookie sheet. Refrigerate 10 minutes. Bake rounds 7 minutes; cool. (Do not prebake additional shapes.)
In large bowl, mix brown sugar, cinnamon, allspice, melted butter and lemon juice. Gently stir in pear slices.
Arrange pear slices in concentric circles on prebaked rounds, stacking pears about 2 inches high; insert 2 skewers in top of each tart to secure pears. Drizzle with any remaining sugar mixture from bowl.
Bake tarts and shapes 15 minutes or until shapes are puffed and golden brown. Remove shapes to cooling rack. Bake tarts 10 minutes longer or until golden brown and slightly caramelized.
To serve, place tarts on dessert plates. Garnish with baked pastry shapes, sweetened whipped cream and nutmeg.