
Mix till fluffy in mixing bowl:
250g butter
200g fine sugar
5 large eggs
Sift in separate bowl:
250g plain flour
40g cocoa powder
1/4 teaspoon sodium bicarbonate
1 teaspoon baking powder
Add sifted flour mix to butter mix, little by little till done.
Add 100g melted cooking chocolate to mixture.
Add 3/4 cup cool water. Mix well.
Meanwhile, preheat oven to 180C.
Pour mixture in baking pan lined with butter paper.
Bake for 45 mins or till done.
For cupcakes, bake at 165C for 15-20 mins or till done (depends on cupcake size).
See here for decorated cakes and cupcakes.