Preheat the oven to 200C/400F degrees
Add the erythritol to the butter and stir well.
Add the eggs and combine thoroughly
Whisk in the peanut flour, baking powder and salt.
In a small bowl, spoon in about 4 tablespoons of the batter.
Add the cocoa powder and blend into a paste.
Add the coconut milk and blend until smooth.
Pour the peanut batter into a muffin tin lined with cases. Pour about 2/3 of the way up.
With a small spoon, drizzle the cocoa mixture into the muffin cases.
Using a knife, place it into the cupcake and gently swirl the cocoa mixture around.
Bake for 20 minutes until firm and golden.