Preheat the oven to 350°F and line an 8x8-inch baking pan with parchment paper, leaving overhang on two sides.
Mix the almond flour, cocoa powder, erythritol, salt and melted butter until evenly moistened. Press firmly into the pan, bake for 10 minutes, then cool completely.
Melt the chocolate chips in the microwave in 30-second bursts, stirring until smooth. Let cool for about 10 minutes, until barely warm but still fluid.
Beat the softened butter, cream cheese and powdered erythritol for 3 minutes until light and fluffy. Beat in the cooled chocolate, cocoa powder, vanilla and salt until silky.
In a separate bowl, whip 1 cup heavy cream to stiff peaks. Fold it into the chocolate mixture in two additions until no streaks remain.
Spread the filling over the cooled crust and smooth the top. Chill for at least 4 hours, until firm.
Whip the topping cream with the erythritol and vanilla to medium-stiff peaks and spread it over the bars. Sprinkle with grated chocolate and slice into 16 bars.