- Preheat the oven to 180 Degrees C. Grease and dust a cake pan. Break the Oreo biscuits into pieces and add them in a grinder. Grind to make a smooth powder. Sieve the powder through a sieve. Mix biscuit power and baking powder in a bowl. Add vanilla extract, oil and 1 cup milk and whisk well to make a lump free batter. Add sugar and ¼ cup milk and mix well. Pour the batter in the prepared pan. Bake for 30-35 minutes. Remove the cake pan from the oven and transfer the cake on a cooling rack. Once cooled, cut into slices and serve.