Place the Oreos into a food processor, and blend until they become fine crumbs.
Add the crumbs to a mixing bowl, and pour in the milk and baking powder. Stir until well combined and smooth.
Spread the mixture into well greased, microwave-safe ramekins, mini loaf pans or any other containers you may wish to use. Fill about ½ – ⅔ of the way full.
Microwave for 2-3 minutes, or until a knife inserted into the middle of the cake comes out clean.
Let the cake cool slightly, then run a knife along the edges to help loosen the cake from the container. Turn the cake out onto a tray to cool completely and spread icing on the top.
Serve and enjoy.