Preheat the oven to 320F / 160C (electric) or 280 F / 140C (fan). Line the bottom of a cake pan with parchment paper and grease the sides to prevent sticking.
Mix the almond flour, sweetener and butter in a bowl to form a dough. Bake for 20 - 25 minutes until slightly golden. Remove from the oven and allow to cool.
Filling
Place the sugar free chocolate chips (or dark chocolate) in a heatproof bowl over a pan of hot water. Simmer on a low heat until melted, stirring occasionally, until glossy and smooth.
Remove the bowl from the heat and allow to cool slightly.
Whisk the mascarpone, cream cheese, heavy cream, sweetener, vanilla and a pinch of salt together in a bowl using an electric whisk until thick but don’t over beat. Slowly pour in the melted chocolate and fold in with a spatula to combine. If using an electric whisk, use a slow setting and don’t over-beat the filling or it will go stiff. Adjust the sweetness to taste.
Spoon the chocolate filling onto the crust and level with a spatula.
Chill in the fridge for at least 3 - 4 hrs or overnight until set.
Ganache
Heat the cream and butter on a low heat until hot (but not bubbling). Turn off the heat and add the chocolate. Allow to stand for 3 - 5 minutes until melted. Stir briskly with a balloon whisk until glossy and smooth.
Spread over the top of the cheesecake and top with grated chocolate. Option to put the cake in the fridge if you prefer a set ganache.
Video
Notes
Net carbs 7.2g per 1 slice of 16. As this cake is very filling, you could consider cutting into 20 servings. Then, 1 slice would be 331 calories, 14.2g total carbs and 5.8g net carbs. FYI - if you cut into 20 slices and used 85% chocolate instead of sugar free chocolate chips, nutrition changes to 366 calories, 7.3g net carbs per slice and 5.3g sugar. Serve with a drizzle of cream or sugar free vanilla ice cream.Storage: Fridge for up to 4 days or freezer for 2 months and defrosted at room temperature.You can serve this cake straight from the fridge or leave on the counter for 1 hour to soften the frosting.