Ensure cream cheese, eggs, and sour cream are at room temperature.
Finely chop nuts (not into powder) and mix with sugar and cinnamon and set aside.
Beat together sugar, vanilla, and cream cheese until smooth.
Add sour cream, lemon juice, and zest (if using).
Beat until smooth.
Add eggs and mix until just combined.
Pour the mixture through a sieve to remove lumps. Set aside.
If using thick ghee, warm it until liquid.
Use a 9" or 10" round springform pan, lining the bottom with parchment paper.
Layer 10 sheets of phyllo in the pan, brushing each with ghee.
After the tenth layer, sprinkle half of the nut mixture over it.
Layer 5 more sheets, brushing each with ghee, then add the remaining nut mixture.
Finish with another 5 sheets of phyllo.
Pour the cheesecake filling into the prepared phyllo crust.
Scrunch the edges of the phyllo into a ruffled shape.
Bake at 325°F for 60-70 minutes on a sheet pan.
In a small pot, cook water, sugar, honey, and a pinch of salt over medium heat, stirring until sugar dissolves.
Cook for about 7 minutes until slightly thickened.
Add lemon juice if desired.
Pour the syrup over the baked cheesecake, focusing on the sides.
Optionally, sprinkle with chopped nuts.
Cool, then chill overnight.