1. Preheat your oven to 190°C / 375°F.

2. In a large mixing bowl, combine the cold butter and flour. Gradually add the ice-cold water while gently mixing until the dough comes together. Wrap it in plastic wrap and refrigerate for 30 minutes.

3. On a lightly floured surface, roll out the chilled dough to a thickness of about 3 mm / 1/8 inch. Transfer it to a 23 cm / 9-inch pie dish, trimming the edges to fit. Brush the edges with the beaten egg for a golden glaze.

4. In a separate bowl, whisk together 3 eggs, heavy cream, dried oregano, dried basil, salt, and black pepper. Pour the mixture into the pie crust.

5. Arrange the sliced tomatoes on top of the egg mixture, slightly overlapping each other.

6. Sprinkle the grated mozzarella cheese evenly over the tomatoes.

7. Bake the pie in the preheated oven for 40-45 minutes or until the crust is golden brown and the filling is set.

8. Remove the pie from the oven and let it cool for 10-15 minutes. Garnish with chopped fresh parsley if desired. Serve warm and enjoy!