1. Preheat the oven to 180°C (350°F) and place the rack in the bottom of the oven.

2. In a large bowl, mix the pear segments with the lemon juice, 60 ml (1/4 cup) of sugar, 250 ml (1 cup) of caramel, the cornstarch and the cinnamon. Set aside.

3. Divide the pie dough into two equal parts. On a floured work surface, roll out one part of the dough into a 35 cm (14 in) diameter circle. Roll out the remaining part of the dough into a 24 cm (9 1/2 in) square.

4. Place the circle of dough in a deep tart pan 23 cm (9 in) in diameter and 5 cm (2 in) thick. Transfer the pear mixture into the pan and smooth the surface.

5. Cut ten equal strips from the square of dough. Cover the pear mixture with the strips of dough to form a lattice. Press the edge to seal the two doughs.

6. In a small bowl, whisk the egg yolk with the milk. Brush the top of the dough with the beaten egg yolk, then sprinkle with the remaining sugar.

7. Bake for 1 hour 10 minutes to 1 hour 20 minutes. Remove from oven and let cool.

8. Garnish the tart with the remaining caramel.