Start by placing the oreos in your mug (or another container, if that’s more convenient), and crush them well until they’re finely crumbled. You can use a fork to break up the oreos.

Add the milk and start mixing well. Use the fork to break up the oreo pieces well and obtain a homogeneous mixture. The more you grate the oreo, the softer your cake will be!

Now, the best part! Drop 1 tablespoon of Nutella right in the middle of the batter. Do not stir! This will create a gooey Nutella center when cooked

Microwave the mug on high for 60-90 seconds. What I do is leave it in the microwave for 60 seconds and take a look, if the cake hasn’t risen much, I add another 30 seconds (which was the case).