In a medium saucepan, combine the milk, butter and golden syrup. Bring to the boil and whisk in the Bi-Carb Soda until smooth. Set aside to cool.
Preheat the oven to 180oC/160oC fan-forced. Line a 12-cup capacity muffin tin patty cases and set aside.
In a bowl, combine the flour, oats, baking powder, brown sugar and coconut.
Add the egg into the cooled milk mixture and whisk until combined.
Fold the wet ingredients into the dry ingredients, folding until just combined and moist. Divide the mixture evenly between the cupcake cases.
In a small bowl, combine the brown sugar and oats for the topping. Sprinkle topping evenly over each muffin cup. Bake for 15 - 20 minutes.
Cool in the tin for 5 minutes and then let cool on a wire rack.