Preheat your oven to 350°F (175°C) and grease a 9-inch round cake pan or line it with parchment paper.
In a large mixing bowl, combine the almond flour, cocoa powder, erythritol, coconut flour, baking powder, instant coffee granules, and salt. Mix well to ensure all dry ingredients are evenly distributed.
In a separate bowl, whisk together the melted coconut oil or butter, unsweetened almond milk, and vanilla extract until smooth.
Pour the wet ingredients into the bowl with the dry ingredients. Stir until just combined and a batter forms. Be careful not to overmix.
Fold in the melted sugar-free dark chocolate chips until evenly distributed throughout the batter.
Transfer the batter to the prepared cake pan and spread it evenly.
Bake in the preheated oven for 25-30 minutes, or until a toothpick inserted into the center comes out clean.
Once baked, remove the cake from the oven and allow it to cool in the pan for about 10 minutes before transferring it to a wire rack to cool completely.
While the cake cools, prepare the frosting by whipping the heavy cream or coconut cream until soft peaks form. Gradually add the powdered erythritol and vanilla extract, continuing to whip until stiff peaks form.
Once the cake is cool, frost the top with the whipped cream mixture. Garnish with toasted almond slices, a dusting of cocoa powder, and fresh raspberries for a beautiful presentation.