Preheat the oven to 180C/350F degrees.
Mix the hazelnut flour, baking powder and salt together.
In another bowl mix the butter, eggs and low carb sweetener.
Combine the wet and dry ingredients together, and stir well.
Pour the mixture into cupcake cases in a muffin/cupcake tin.
Bake for 20 to 23 minutes until firm.
Whilst the cakes are cooling make the cream cheese topping.
Blend the butter, cream cheese, coffee, coconut milk and low carb sweetener in a bowl until smooth and creamy.
Smother (or pipe if you are neater) the topping over the top of the muffin.
Eat and enjoy!