With the rack in the middle position, preheat the oven to 190 °C (375 °F).
Line a baking sheet with parchment paper.
Roll out the dough into four 10-cm (4-inch) squares. Brush with the milk and sprinkle with the sugar. Place the squares on the baking sheet. Bake for 15 minutes or until the pastry is golden brown. Allow to cool.
Meanwhile, in a large skillet, melt the butter and sugar over high heat until the sugar turns golden brown. Add the pears and sauté for 4 to 5 minutes or until they brown slightly and are tender. Keep warm.
Place the chocolate in a bowl. Set aside.
In the same skillet, heat the sugar until it turns a light golden hue. Be careful not to burn. Add butter and cream and stir until the mixture is smooth. Pour the caramel over chocolate and whisk until the mixture is smooth.
Place the pastry squares on four plates.
Garnish generously with pears and add a scoop of ice cream. Drizzle with the chocolate sauce and sprinkle with hazelnuts.