I stayed at the MIJE Fauconnier for more than 10 nights totally. Everything is ok except the breakfast service. The lady is the most rude stuff I have met in my two months Europe trip, and ruins all the good points of this hostel. Her English accent is not so easy to understand, that's ok, but she is ALWAYS irritable and impatient with repeating a simple question, even there is no other guests waiting and she is not busy. She treated the guests seems like we are beggars and forgot we got the breakfast cause we paid the room fees. She should know she got the salary is because of these guests not her boss.
I noticed that there are other guests complained the same problem several years ago on Tripadvisor. If this lady hates her job and people, then she is apparently not qualified to do this job and you put a wrong person at a wrong position. Several years passed by, the problem is still not resolved. It's not easy to change an elder woman/man. The only way to solve the problem is to change a breakfast waiter/waitress, or the service mode. Don't let her face the guests, since she is not good at this. Maybe cancel the breakfast and reduce the room fare is a good idea, that would make you more competitive.
I gave up the breakfast hereafter, if it is your real purpose, you made it. If you don't improve the situation, I would not recommend anyone to this hostel, because no one would like to be disrespected, not to mention being treated as a beggar.