Preheat the oven to 350°F (180°C) and line the bottom of two small, (approx. 9 inches) round springform pans with baking paper.
Combine the softened butter with the Erythritol and beat with an electric mixer until fluffy.
Beat in the egg, vanilla, sour cream, and vinegar.
In a mixing bowl combine the almond flour with the cocoa powder, baking soda and a pinch of salt. Fold into the butter mixture.
Add a few drops of red food coloring until you get the desired shade of red.
Divide the mixture into the prepared pans and bake in the preheated oven for 20-25 minutes. Allow them to cool to room temperature.
Slice each cake in half horizontally, with a bread knife.
Make the frosting by whisking together the cream cheese and the powdered Erythritol.
Frost each layer of the cake and cover the sides as well. You don’t have to be precise with the frosting!
Slice and serve at room temperature.