I am sharing here microwave method.
firstly grind the Oreo and parle g biscuits like powder and empty in a large bowl.
Add sugar and milk in the mixture and mix well.(note : add milk slowly)
Check the batter consistency.
Add eno and mix well.
Grease the microwave mould with butter and pour the batter in microwave mould.
Now put the mould in microwave and set the microwave at high temperature for 5 minute.
After 5 minute take out the cake and put a toothpick or knife in it. If it comes out clean, your delicious cake is ready.(note: If knife or toothpick is messy then cook for 1 minute more)