Preheat oven to 190 C degrees.
Melt the butter and let it cool.
Set 1 spoonful of flour aside and place the rest in a large bowl. Add the baking powder, salt, spices and cocoa powder.Combine well.
Whisk the egg lightly, then stir in the cooled butter and milk.
Coat the raisins & walnuts with the flour you've set aside, then add them to the egg mixture and combine gently.
Add the egg mixture to the flour mixture, mix gently with a wooden spoon.
Spoon the batter into muffin tin lined with paper cups or into silicone muffin cases.
Bake the muffins for 25 minutes until golden.
Let them cool in the tin/cases for 5 minutes, then move them to a wire rack.
When completely cool, decorate them to your liking.