Preheat your oven to 350°F (175°C). Combine the graham cracker crumbs, cocoa powder, granulated sugar, and melted butter until well blended.

Press the crust mixture firmly into mini muffin tins lined with cupcake liners.

Beat the softened cream cheese in a large mixing bowl until smooth. Gradually add sour cream, granulated sugar, and vanilla, blending until fully combined.

Spoon or pipe the cheesecake mixture over each crust until they are three-quarters full.

Bake for 15-18 minutes until set but slightly jiggly in the center. Cool at room temperature, then refrigerate for at least 2 hours.

Whip the heavy cream until soft peaks form and spoon or pipe it over each cheesecake cup.