Grease the bottom and sides of a 9 inch springform pan with the butter and press in a large sheet of parchment paper. Once the parchment is pressed in tightly, add another large sheet in the opposite direction, creating a 2-inch overhang around the pan.

Into the bowl of a stand mixer, add the cream cheese and mascarpone, and mix on medium-low speed with the paddle attachment until smooth.

Reduce speed to low and gradually add the granulated sugar. Increase the speed to medium and continue to blend until smooth, scraping down the sides of the bowl as needed.

With the mixer still running, add the eggs and egg yolk, one at a time.

Add the sea salt, heavy cream, vanilla extract and orange blossom water. Mix until smooth, stopping the mixer often to scrape down the sides of the bowl.

Turn off the mixer and sift the flour directly into the bowl. Mix on medium speed until incorporated.

Pour the cheesecake batter into the prepared pan.

Carefully place the pan onto a baking sheet and bake until the top is dark brown, about 60 minutes.

Remove the cheesecake from the oven and leave it in the pan for a few minutes.

Once the surface of the cheesecake has gently collapsed, release the springform pan and let the cake cool completely.

Serve at room temperature.