Preheat oven to 180C or 350F.

Chop butter and chocolate. Better if both are in room temperature. Powder the sugar.Please refer notes if you wanna use normal sugar instead of caster sugar.

Combine butter, chocolate, sugar and milk in medium saucepan. To be safe, you can use a double boiler.

Mix it well and stir over low heat, without boiling, until smooth.

Let it cool down. It might take around 15 minutes.

Transfer mixture to a large bowl. Mix flour and baking powder. Whisk it in the above mixture.

Add essence and eggs. Whisk it until batter is smooth.

Line the baking pan with parchment paper.

Pour the batter into the pan, Cover the pan with aluminium foil and bake for about 1 hr or until a toothpick inserted in the centre comes out clean.

That's the cake. All ready.

To prepare white chocolate ganache, make sure that chocolate is chopped into small pieces. I prefer to melt the chocolate for 30s in oven so that it gets mixed with cream easily.

Bring cream to a boil in a small sauce pan. Pour over chocolate and stir with a spoon until chocolate melts completely. Cream and chocolate should get mixed well.

Cover the bowl, refrigerate, stirring occasionally, about 30 minutes or until ganache is of a spreadable consistency.

Place the cake on a serving plate. Spread the ganache over top and sides of cake. Wait for the ganache to set. Store in the refrigerator. Enjoy :)