Preheat oven to 325°F (163°C).
Prepare the springform pan by lining the bottom with parchment paper and brushing the sides with coconut oil or spraying with non-stick spray.
Wrap the bottom of the pan in aluminum foil to prevent water seepage during the water bath.
In a large bowl, cream Neufchâtel cheese using a whisk or stand mixer on low speed.
Add eggs one at a time, mixing after each addition.
Mix in Greek yogurt, pumpkin puree, and vanilla extract until well combined.
Add whey protein powder, stevia, and pumpkin pie spice to the batter.
If there are visible air bubbles, gently tap the bowl on the counter.
This helps eliminate the air bubbles, which can affect the cheesecake texture.
Pour the mixture into the prepared pan, place it in the larger pan in the oven.
Add about 1 inch of water for the water bath, and bake at 325°F for 30 minutes.
Lower the oven to 200°F (93°C) and bake for an additional 65 minutes.
The cheesecake should be set around the edges with a slight jiggle in the center.
It should not brown at the edges.
For best results, do not open the oven door during baking.
Let the cheesecake cool at room temperature before refrigerating. It needs a few hours in the fridge to fully set.
Refrigerate for several hours or overnight.
Remove from springform pan and serve.