Preheat the oven to 165 degrees.
Crush the cookies in a mixer grinder and keep them aside.
In a bowl, flour, oreo cookies mix, baking powder, cocoa powder, vanilla essence, sugar, and oil. Mix well. Add one beaten egg and mix well.
To this mix, gradually add hot milk to bring the right consistency. First add 1-2 a cup. If the mixture is not upto thick flowy consistency then you may add another tbsp milk to get the right consistency.
Mix this mixture well.
Grease the pan with clarified butter or butter and transfer the mix. Tap it on the shelf to release bubbles if any.
Bake @ 165 degree C, for 30-35 minutes. The time may vary per oven, please check the brownies in between. Overbaked brownies lose the right texture.
Recipe Notes
Use a bread loaf pan or a brownie pan.
For a Vegan Variation: replace the Milk with coconut/ soya milk.