**Make the Syrup:**

1. While the custard cools, make the simple syrup. In a pot over medium heat, combine water, sugar, and orange blossom water.
2. Bring to a boil to dissolve the sugar, then reduce the heat and simmer for 10 minutes.
3. Transfer to a bowl and let it cool to room temperature to thicken.

**Make the Custard:**

1. In a mixing bowl, whisk together the eggs and 1/3 cup sugar until lighter in color. Set aside.
2. In a pot over medium heat, add heavy cream, milk, sugar, salt, cornstarch, semolina, and vanilla extract.
3. Whisk continuously and bring to a boil. Once it starts bubbling, lower the heat and simmer, whisking constantly, until it thickens.
4. Remove from heat and stir in the butter.
5. Slowly mix a bit of the hot custard into the egg mixture to temper the eggs, then combine all the custard and mix until smooth.

**Assembly and Bake:**

1. Preheat the oven to 350°F.
2. Take out the phyllo sheets and cover them with a damp towel to keep them from drying out.
3. Brush the bottom of a 9×13 tray with melted butter. Add a phyllo sheet, letting the sides hang over the edges of the pan.
4. Brush the phyllo sheet with butter and add another sheet on top. Repeat until you have 9 to 10 sheets stacked.
5. Pour the custard on top of the phyllo sheets, then repeat the butter and phyllo layering until you have another 9 to 10 layers.
6. Cut the assembled pie into 12 equal pieces with a sharp knife.
7. Bake for 45 to 50 minutes until the top is golden and crispy.
8. Remove from the oven and immediately pour the simple syrup over the top. Use as much or as little as you like.
9. Garnish with chopped pistachios and rose petals.
10. Let the syrup soak in for at least an hour before enjoying!