Melt the chocolates bar by using double boiler method. Note: For boiling fill idli vessel with water as required and accordingly place bowl with chocolates for melting.
Grind Biscuits until powdered finely.
Transfer the fine powdered biscuits into a bowl and add half cup of milk , mix well until flowing consistency.
Now take idli mould grease it with oil and pour 1 tablespoon of mixture following with some melted chocolate ontop and cover again with 1 tablespoon of mixture. Same way fill all idli mould in same manner and steam for 10 minutes.