Preheat the oven to 400 degrees.
To prepare the puff pastry crust, take the thawed dough and place it on an ungreased baking sheet.
Fold the dough in half so that it makes a triangle.
Using a sharp knife make a slice one inch from the edge of the crust up each short side of the triangle.
Unfold the dough back into a diamond.
Take one side of the cut dough and fold to the opposite corner.
Repeat on the following side so that the dough is now a diamond with a twist at the top and bottom.
Thinly slice and peel (if desired) the pears and plums.
In a medium bowl, gently toss the pears and plums with the lemon juice, sugar, and cornstarch.
Arrange the sliced fruit in the center of the pastry dough.
Discard any leftover liquid from the fruit.
Bake at 400 degrees for 15-20 minutes, or until puffed up nicely and golden brown.
In a small bowl whisk together the jam and the honey.
Microwave 20 seconds to melt the jam.
With a pastry brush, brush the glaze over the entire galette, filling and crust.
Serve warm with ice cream or allow to cool completely.