Prepare the crust: Preheat the oven to 325°F (163°C). In a medium bowl, combine the almond flour, melted butter, and granulated erythritol until a crumbly dough forms. Press the mixture into the bottom of a 9-inch springform pan, creating an even layer. Bake for 10-12 minutes or until lightly golden. Remove from oven and let cool.
Make the filling: In a large mixing bowl, beat the softened cream cheese with an electric mixer until smooth. Add the peanut butter and powdered erythritol, and continue beating until well combined and creamy.
Add the remaining ingredients: Mix in the sour cream and vanilla extract. Then, one at a time, add the eggs, beating well after each addition until the ingredients are fully incorporated and the mixture is smooth.
Combine: Pour the filling over the cooled crust and smooth the top with a spatula.
Bake the cheesecake: Bake for 45-50 minutes, or until the edges are set but the center is still slightly jiggly. Turn off the oven, open the door slightly, and let the cheesecake cool inside for 1 hour to prevent cracking.
Chill: After cooling, refrigerate the cheesecake for at least 4 hours, preferably overnight, to set completely.
Garnish (optional): Before serving, sprinkle the top with chopped roasted peanuts and sugar-free chocolate chips for extra crunch and flavor.
Serve: Slice the cheesecake and serve chilled.