Chocolate concrete tips?

[jwalk]

I've attempted to make chocolate concrete using this recipe a few times now and while the first batch came out perfect most batches after that haven't been up to scratch. I think there's a problem with the texture of them but I can't quite figure out what I'm doing wrong.

Has anyone here made chocolate concrete before? Any tips or pointers you could offer me?

 

[MNasiruddinZ]

I never do it, but look like delicious to me.. if there have chocolate, I like it.. hope someone here will give us tips or advice to do it.