Prep the pan. Line the bottom of a 9-inch springform pan with parchment. Lightly grease the sides with butter or oil. Preheat the oven to 325°F (163°C).

Make the crust. In a bowl, whisk almond flour, cocoa, sweetener, and salt. Stir in melted butter and vanilla until it resembles damp sand. Press firmly into the bottom of the pan in an even layer.

Par-bake the crust. Bake for 8–10 minutes until set and fragrant. Let it cool while you make the filling.

Beat the cream cheese. In a large bowl, beat softened cream cheese on medium speed for 1–2 minutes until smooth and fluffy. Scrape the bowl to avoid lumps.

Add dry ingredients. Sift in powdered sweetener, cocoa powder, espresso powder (if using), and salt. Beat on low until combined, then on medium until creamy.

Mix in liquids. Add vanilla, sour cream, and heavy cream. Beat on low just until smooth. Avoid overmixing to reduce air bubbles.

Add eggs last. Beat in the eggs one at a time on low speed. Mix only until incorporated. Overbeating can cause cracks.

Fill and smooth. Pour the batter over the cooled crust. Tap the pan gently on the counter a few times to release trapped air.

Bake low and slow. Bake at 325°F (163°C) for 45–55 minutes. The edges should be set and the center slightly jiggly, like set Jell-O.

Cool gradually. Turn off the oven, crack the door, and let the cheesecake sit for 30 minutes. Then cool on the counter for 1 hour before refrigerating.

Chill fully. Cover and chill for at least 6 hours, preferably overnight. This sets the texture and deepens the flavor.

Optional ganache. Warm heavy cream until steaming, then pour over chopped sugar-free chocolate. Let sit 2 minutes, then whisk smooth. Sweeten to taste. Spread over the chilled cheesecake and let set 20 minutes.

Slice and serve. Run a thin knife around the edge before releasing the springform. For clean slices, use a hot, dry knife and wipe between cuts.