Preheat oven to 180˚C.
Place the cupcake mix, eggs, water and vegetable oil in a mixing bowl. Mix at high speed for 1 minute.
Place paper cups in muffin mould. Scoop batter into paper cups, about 2/3 full.
Bake for 15 minutes, then set aside to cool.
Break cooking chocolate into pieces. Melt cooking chocolate with microwave (2 minutes, medium high) oven or over a saucepan.
Spread melted chocolate onto the cupcake, sprinkle with hundreds and thousands.