Went here for a whim for dinner on our second night here and found it to be pretty good. It's a charming little cafe with a small front room and kitchen upstairs. The service wasn't that great as it took some time for them to even notice we had arrived, but not enough to really complain about.
I had the fish of the day, which I was told was Halibut but found out later was actually sea Trout (which was fine too) on a bed of vegetables and some potatoes on the side. The fish was tasty, and the vegetables were...well, they were just vegetables. I don't know what they did to the potatoes, but they tasted amazing. My partner had a pepperoni pizza, which looked good and tasted good as well.
Had the chocolate cake and ice cream, as well as the skyr panna cotta with berries for dessert. They were both just all right, nothing special.
Not the cheapest meal (a common theme here in Reykjavik), cost around $50 total.