Preheat oven to 200 deg Celsius. Lightly grease the muffin pans and line with muffin cups if desired. Melt the butter over low heat in a saucepan. Leave it aside to cool.
Separate the durian pulp from the seed. Use a fork and mesh it until it’s creamy. Add egg, milk and half of the durian pulp to the cooled butter. Stir until well combined.
In another bowl, mix the dry ingredients – flour, sugar, salt, baking powder together. Make a well at the centre and slowly pour the liquid mixture in.
Mix until the wet and dry ingredients are just combined. Do not overmix as this will produce hard muffins. The batter should be lumpy and not too liquidy.
Spoon about 1 tablespoon of the batter onto one muffin cup. Put a tablespoon of durian pulp on top of the batter and top it with another tablespoon of batter. Do the same for the remaining muffin cups.