While hiking in Warsaw, you need a coffee break. I recommend with my whole heart to look for local cafes, which will be one of a kind experience.
However if you insist on an internarionally known chainstore, why not choose a cafe with a difference?
There is a S*******s cafe on the corner of Plac Trzech Krzyży. When you enter and decide to have a coffee there, you can admire some historical graffiiti from the 1950s.
The cafe was a part of the landscape since the latter part of 19th century, but its heyday falls on the 50s, when the place became a centre of literary and artisitc life of those times: poets, painters, scenograpgers, sculpturers...
Some of them started to decorate the interiors with pictures presenting the guests of the cafe, their caricatures, cartoons...
After a time, though, the place was changed into a restaurant then into a boutique... The graffiti were covered under new layers of paint and they fell into oblivion.
...almost. A few years ago when the afore-mentioned chainstore decided to set up a branch here, they also decided to recover the forgotten paintings and renovate them. (I suppose it's a rare instance of a situation when an international corpo takes care of the local heritage... here at least).
Fancy a coffee?
