Melt the butter in the microwave.
Add in the whipping cream, erythritol and instant coffee powder and mix well
Microwave another 15-20 seconds if needed to dissolve the coffee
Add the vanilla, a pinch of salt and egg and mix well
Then add in the baking powder, almond flour, psyillium husk, cocoa powder and stevia and mix till you get a nice smooth batter.
Transfer to two ramekins or mugs and microwave for a minute each
Top with the vanilla mascarpone frosting or whipped cream and enjoy!