Roll out the pastry dough into a large circle and transfer to a baking sheet that has been lined with parchment paper.
Combine the ricotta cheese and the mozzarella cheese.
Combine the olive oil with the Italian seasoning. Add half of this to the ricotta and mozzarella cheese and mix well.
Spread the cheese mixture on top of the pastry dough being careful to leave a 2 inch border.
Arrange the zucchini on top of the cheese mixture attractively.
Drizzle the remaining olive oil and herb mixture on top of the zucchini.
Fold the border of dough up around the zucchini filling leaving the center of the galette open.
Brush the crust with the egg wash.
Sprinkle the edge of the dough with freshly grated Parmesan cheese.
Bake for about 45 minutes or until the crust is golden brown in a preheated 400 degree oven.