Line four 4-inch tart dishes with the puff pastry. Lightly prick the surface with a fork. Sprinkle the blue cheese crumbles on top of the pastry-lined dishes. Top the blue cheese crumbles with walnuts. Place pear slices decoratively on top of the walnuts. Brush the pears with melted butter. Bake for 30 minutes or until pastry is golden brown. Drizzle with caramel sauce and serve with a scoop of vanilla ice cream.