Step 1

Preheat oven to 180°C. Brush twelve 80ml (1/3-cup) capacity muffin pans with melted butter to lightly grease.

Step 2

Combine cocoa and hot water in a bowl and stir until smooth. Add the egg, egg white, sugar, yoghurt, apple puree, milk and vanilla, and whisk until well combined. Stir in the chocolate until combined.

Step 3

Sift flour over the mixture and use a large metal spoon to fold until just combined. Spoon mixture evenly among prepared pans. Bake in preheated oven for 20 minutes or until a skewer inserted into the centres of the muffins comes out clean. Remove from oven. Set aside in the pans for 5 minutes before turning onto a wire rack to cool.

Step 4

Dust with icing sugar to serve.