Raspberry cupcakes

After the cupcakes I made for my mother in law, I baked others, also using a ready mix but to be honest, they were not special at all, they didn't have that "yummy" factor... so I had to try making my own from scratch...yes!.
I was looking for easy recipes to start with and I found this one , Raspberry cupcakes....hmm!!

I don't know why, they sank in the middle, could have been too much moisture from the raspberries? if you have an idea of what went wrong here please let me know, I'll really appreciate it :o)

The taste was great, but that hole in the middle didn't look good....I had to save them!...so I melted some chocolate and poured on top, then I garnished with some rainbow white chocolate buttons: