Lokal Unas is part of an interesting space called Possonium which offers a space for a couple of street-food restaurants and a cafe/bar under a single roof, as well as offers accommodation in modern apartments. Its main asset is the big courtyard with trees, which offer good shade to rest in, especially during the hot summer days.
I like to get a lemonade as a refreshment, and their excellent burger when I’m hungry. During weekdays, I often opt for their lunch menu which includes soup and a choice between three different main dishes (usually one is local Slovak food, another one international food and the last one is vegetarian or a salad).
Although it is on the edge of Bratislava’s Old Town, it is located close to a big crossroads of public transport, so you can either take a tram or a bus and reach the city center very quickly. Plus, it is just down the hill from the main train station.