This is what would have happened if McDonald's had started out as a French company.  (To see what happens to McDonald's when it acquires a French accent, click here.)
La Brioche Doree is a chain of pastry shops stretching from Cape Town to Miami.  The coffee is strong enough to give you the shakes while you're still seated.  The pastries are...  French, definitely French.
Apres-midi they turn into quiche shops ("Sorry, breakfast is only served until 2pm...") serving up single slices that you can take home for supper.
We discovered one of these only a few blocks from our apartment and right around the corner from Cluny.  We ate breakfast there several times and brought supper home as well.  Purists will turn their noses up ("You ate where ?????") but we liked it.
Like all Parisian businesses, you'll do fine if you know "Bonjour" and "Q'est-ce que c'est?".  They recognize instantly (from the accent, I suppose) that you don't know beans about French and switch to a language you're more comfortable in...  usually English.
It's not the only choice, of course.  You can also pick up breakfast at any one of the millions (possibly trillions) of boulangeries and patisseries scattered around Paris like birdseed in the park.  Like this street vendor who made crepes to order while-you-wait...