Preheat your oven to 350°F (175°C). Wrap the bottom and sides of a 9-inch springform pan with foil—this trick helps prevent any leaks!
For the crust, combine the pecans, melted butter, and 2 tablespoons of sweetener in a food processor or blender. Pulse until the nuts are finely chopped. Press this mixture firmly into the bottom and about half an inch up the sides of your prepared springform pan. Bake for just 10 minutes.
While the crust bakes, let's make the creamy filling! In the same food processor (no need to wash it!), pulse the softened cream cheese and cottage cheese until perfectly smooth. Scrape down the sides as needed. Then, add the pumpkin puree, eggs, 1 cup of sweetener, and cinnamon. Blend everything until it's wonderfully smooth and lump-free.
Carefully pour the smooth pumpkin filling over your partially baked crust. Bake for 1 hour to 1 hour 15 minutes, or until the edges are beautifully golden brown and the very center only has a slight jiggle. Let it cool completely to room temperature, then transfer it to the refrigerator to chill for at least 3-4 hours (or even better, overnight!). This helps it set perfectly.
For an optional delightful topping, whip the heavy cream until soft peaks form. If you like, gently fold in 2 tablespoons of sweetener. Spread this lovely whipped cream over your thoroughly chilled cheesecake. Store any leftovers in the refrigerator.