Hey slepax, I can think of three possibilities off the top of my head.
- First, you could have cooked your egg yolks with the heat from the cream, which would definitely give you a lumpy texture. There's not really much you can do about cooked egg, unfortunately - on the plus side, this mixture can still be used in cookies!
- The second option is that your chocolate has seized; this happens when chocolate comes into contact with water, but it doesn't usually happen when blending with cream - it's possible that if you just slowly heat the mixture back up, it will smooth out. Alternatively (if seizing is the issue) you can add a tablespoon more of hot cream to see if it helps, or even a spoon of melted butter; this helps break up the syrup that is created when water mixes with the sugar in the chocolate.
- Finally, you might have just heated the mixture too much! At which point you'd need to cool it down, and remelt it with fresh chocolate and a bit of butter(if you're trying to salvage it, but overheated chocolate can still be used in chocolate chip cookies as well). You could even try blending it all together gently with a hand held blender.
Sometimes, you're better off to start over with chocolate, than taking the chance of making it worse as you try to salvage the situation.
For future reference, there are several other ways you could have tried to combine these ingredients that tend to result in less potential for disaster. I tend to use method this method: blend the melted chocolate with the egg yolks first (one at time, and let the chocolate cool a bit first!), AND THEN slowly incorporate the cream a little bit at a time.
Finally, if your recipe also includes sugar, you can whisk up the egg yolks with sugar to help protect against the possibility of cooking the eggs. Combine the eggs and sugar, and then add the melted chocolate, and finally the cream a little bit at a time. This tends to be the most stable way, in my experience, to mix these ingredients together. The heat is there to make it easy to blend, so it never hurts to let things cool just a bit before mixing (ie. hot but not scalding)
'Hope this helps! BTW, what are you trying to make?