In a medium saucepan, combine honey, water, granulated sugar, lemon juice, and orange blossom water. Bring to a boil, then reduce to a simmer for about 10 minutes until it thickens slightly. Remove from heat and let cool.

Preheat your oven to 325°F (163°C). Grease a 9-inch springform pan with butter, line the bottom with parchment paper, and wrap the outside with aluminum foil.

Unroll thawed phyllo dough. Brush the first sheet with melted butter and place in the prepared pan. Repeat with 10-12 sheets, brushing each layer with butter. Mix shelled pistachios with sugar and cinnamon if desired, then sprinkle over the phyllo layers.

In a large bowl, beat cream cheese until smooth. Gradually add granulated sugar and mix. Incorporate eggs one at a time, blending after each addition. Finally, mix in vanilla extract and sour cream.

Pour the cheesecake filling over the pistachio layer. Layer another 10-12 sheets of buttered phyllo on top, folding edges to enclose the cheesecake. Brush the top with melted butter.

Bake in the preheated oven for 60-70 minutes until the edges are set and the center has a slight wobble. Cool for about 1 hour at room temperature before transferring to the refrigerator.

Chill for at least 4 hours. Remove from pan, drizzle with honey syrup, and garnish with additional pistachios.