Preheat the oven to 180°C/Fan 160°C/Gas 4 and line a 12-hole muffin tin with paper cases.
Measure all the cake ingredients into a large bowl and beat together using an electric whisk until light and fluffy.
Spoon the mixture into the paper cases and bake for 20–25 minutes, until golden.
Remove from the oven and transfer to a wire rack to cool.
Meanwhile, to make the icing, place the butter, milk and icing sugar in a large bowl. Beat together using an electric whisk until fluffy and pale.
Once the cupcakes are cool, spread or pipe the icing on top and serve.
Add 25g cocoa powder to the icing and pipe it onto the cakes. Cut ear shapes out of brown fondant and add edible eyes, a jellybean nose and a piece of pink lace for a tongue.
Dip the iced cupcakes in desiccated coconut (you will need about 75g for all 12 cakes). Cut noses, mouths and oval shapes from black fondant and place edible eyes on top. Add mini Oreos for ears.
Turn the icing brown with 25g cocoa powder and ice the cakes, then dip them in chocolate sprinkles. Use half a mini Jaffa Cake for each ear, and a whole one for the face, drawing on nostrils and a mouth with black fondant. Lastly, add edible eyes.