Below are a few suggestions for your lunch breaks.
• Au Vieux Cèdre, 2 Rue Blainville
Very popular grab 'n go Libanese near Place de la Contrescarpe.
Try the falafel sandwich (veggie) and go eat it at the fountain in Place de la Contrescarpe!
• Kaza Maza, 1 Rue de l'École Polytechnique
Another very good street-food Libanese. Try the spinach samossa along with a sandwich, then eat your lunch in Place du Panthéon!
• A nice place to seat? Prêt à Manger, right in Place de la Sorbonne
All sorts of sandwiches, soups and salads.
• Fancy an ice cream? Try Amorino, 18 Rue Mouffetard again next to Place de la Contrescarpe.