Preheat the oven to 200C/180C Fan/Gas 6. Line a 6 hole muffin tin.
In a large bowl, combine the dry ingredients (flour, baking powder, sugar and a pinch of salt).
Make a well and add in the liquid ingredients (melted butter, milk, oil and egg).
Stir together very gently with a wooden spoon, until only just combined. Fold in the chopped chocolate. Spoon the batter into the lined muffin holes, filling to just over 2/3rds full.
Bake 15-18 minutes, until golden on top! Let cool before decorating:
Make the icing in a large mug/small bowl by combining the icing sugar and milk. It should feel really thick - you can test by drizzling a little over a curved surface - it should only move really slowly, if at all when spooned on!
Drizzle a little icing onto the top of each muffin (as pictured). Top with any Easter chocolate that you like!