Preheat the oven to 325°F. Spray an 8-inch round springform cake pan with cooking spray and line with parchment paper.
Make the crust. In a large bowl or stand mixer, combine the almond flour, coconut sugar, and starch. Stir with a wooden spoon until blended. While beating on medium speed, add the melted coconut oil and continue to beat until a crumbly dough is formed, increasing the speed as you need to. Gather the dough and press it firmly in the bottom of the cake pan (it should feel like damp, course sand and should stay compact when you squeeze it). Set aside.
In a high-speed blender, add the cream cheese, sour cream, eggs, peanut butter, erythritol (or granulated sugar or choice), and vanilla extract. Blend until creamy, using the tamper as you need to get the blender going and until everything is smooth.
Pour the filling into the cake pan with the crust. Bake for 50 to 55 minutes until edges have started to turn golden brown and “pull away” from the edges of the cake pan (cheesecake should still “jiggle” and the middle may appear darker, but will set as it cools). Turn the oven off, and open the oven door slightly, and keep the cake in the oven for an additional 30 minutes. Then remove the cake from the oven and allow the cake to cool at room temperature for at least 1 hour before transferring to the refrigerator for 4 to 6 hours (or ideally overnight) to completely set.