Cake in a cup is the best easiest option. I have some advices for that,

1. Use the chocolate or flavoring that the recipe says (not sugared chocomilk or any other variation of flavor or it will have a horrid consistency). True story.

2. Not all of the cups will endure the microwave time.

3. Egg is for the ingredients to stick together. But even 1 egg is too much for the cup. Try to use white thing and not the yellow one because it will taste like egg and that's not nice!

4. If you want to add fruits to id, add them frozen, they will heat in the microwave. Believe me, you don't want burned fruits.

5. For the decoration don't use average whipped cream, it melts too fast.

6. Last but not least, don't over excite too much. Wait until the cake is cold or you'll burn your tongue.....

That's all :D