If you ever find yourself in Berlin, I have to recommend checking out Rausch Schokoladenhaus! Having been a few months ago, I loved my experience. The place smells amazing. Everything about it is clean and polished. They have amazing desserts, fantastic wine, and the coffee is to die for. I am not sure what blend or roast they use, but it has to be some of the best coffee I had ever had. The services it great too. They are very polite. If you love hot chocolate, my sister's nephew says "it is the best hot chocolate in the entire freaking world!". So they have that too.
I never heard about this place for their coffee so I had no idea it was an actual cafe, I assumed it was a small corner spot for treats and light meals. The reason being is that I also heard the hot chocolate is the best in the world. That is because of the chocolate they use, I am sure of it. I have had some of the best from Berlin!
It seems they are known for it if you read other reviews. While I am not much of a hot chocolate fan and care more about the coffee, it is something to be known for something being so good but so simple.