DirectionsAllow 1 piece of puff pastry dough to defrost at room temperature (about 30 minutes).
Place a rack in the middle of oven, and heat to 400 degrees.
Open out the sheet of puff pastry.
On a lightly floured surface, roll it out until it is about 1/8 inch thick.
Cut out a 9-inch circle.
Place on a parchment-covered baking sheet (or a baking sheet covered with greased aluminum foil).
Leaving a 1/4-inch rim, prick the center of the dough all over with the tines of a fork.
With a pastry brush, lightly coat the center of the dough with the milk.
Push 1 tablespoon of the sugar through a coarse sieve to distribute evenly over the center of the dough.
Bake for 5 minutes.
Gently toss the papaya with the lime juice.
Remove the tart shell from the oven, and lay the papaya slices in a spoke pattern on the shell.
Push the remaining 2 tablespoons of sugar through a coarse sieve evenly over the top of the fruit.
Return to the oven for 15 minutes, until the crust is golden and the sugar is caramelized.
Remove from the oven, and slide off the baking pan onto a rack.
Cool slightly and serve, or cool completely and reheat slightly just before serving.
Cut into wedges with large kitchen scissors.