Mash the durian into a smooth paste.
In a bowl, add cake flour, baking powder, sugar and mix them well.
Then, add egg, oil, and milk into another bowl and beat them together using a hand blender or a whisk.
Add the durian paste and mix well.
Add the dry ingredients to the mixing bowl, and mix gently until all the ingredients blend together.
Pour the batter in a baking paper-lined muffin pan or in paper cups made for muffins.
Steam the muffins for 10 to 15 minutes in a steamer.
Cool the muffins using a wire rack and store them in an airtight container.