Preheat oven to 180º C. Grease baking dish with melted butter and dust with some flour. Warm milk in a pan.
In a bowl, add dark chocolate, warm milk, peanut butter. Mix them till chocolate melts.
Then add sugar, raisins, cashew nuts, vanilla essence. mix well. Now sieve maida, baking powder into the chocolate mixture and mix into batter.
Now, pour batter into baking dish, tap little and place it in the preheated oven. Bake for 25-30 minutes, remove, cool brownie on room temperature.
Cut into pieces and place on serving plate. Garnish with raisins and cashew nut pieces and gems.