Asador is the 1st steakhouse I visited in Berlin, I went there on a date a couple of years ago, I went back only once since (too few meat lovers around me) but it still gets great reviews.
They cook Argentinian beef and they cook it good, they also have fish and salad options. By good weather, the terrasse is very nice, I actually never ate inside. The beef is grilled as you wish, it’s very tasty, the service is pretty good, the staff friendly and professionnal. Price range is cheap for a steakhouse of that quality.