We went to Belthazar twice during our stay in Capetown and we had two quite unequal experiences:
During the week we had one of the best meals I ever had in a restaurant. We had a nice table outside. The waiter was polite, fast and very knowledgeable. We had the best steak ever (try pepper-crusted!) and a very tasty game kebab, both cooked to our liking, sauces and sides were great. The free starter was a nice touch as well!
Because of that we came back on our last night in Capetown which was a Sunday. We were able to reserve a table the same day for a quite late seating (around 8:30), good service. But once we got there, the performance was just not comparable to our first night. Everybody seemed to be under a lot of stress, we had to flag down waiters to order drinks and steaks, the free starter was forgotten (although other tables received it around us) and the steaks (ordered medium rare) were cooked blue/rare (cold inside), potato arrived without sour cream.
So, if you are in town on a weeknight, I would definitely recommend Belthazar (5 stars), you will have a lovely dinner. For the weekends they must work something out (3 stars, so 4 stars on average).
One more thing: The wine list is absolutely oversized (literally, it is bigger than a newspaper). This looked probably like a great idea on paper, but it is really not comfortable for the guests.
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