In a small bowl, whisk together the almond flour, cocoa powder, and sweetener. Stir in the butter until the mixture resembles coarse crumbs.
Press into the bottom and partway up the sides of a 4-inch springform pan. Or use a shallow 5 inch fluted ramekin to resemble a mini tart (press the mixture all the way up the sides of the mini ramekin).
In a small microwave safe bowl, melt the chocolate and butter together (this should only take 30 seconds to a minute).
In a medium bowl, beat the cream cheese, sweetener, and cocoa powder together until well combined. Add the melted chocolate and beat until well combined. Beat in the cream and vanilla extract until smooth. The mixture should be a spreadable consistency. If it isn't, add a bit more cream.
Spread the filling in the crust, taking care not to dislodge any of the crust. Refrigerate 1 hour.