One of my favorite bread bakeries in Paris is L’Autre Boulange. Located a short walk from the Marché d’Aligre, the bakery features a lovely selection of wood-fired breads, and others with Nordic roots. The baguettes are also excellent, as are the rustic French pastries.
43, rue de Montreuil (11th)
12, place de la Nation (12th)
Note that the bakery on the rue de Montreuil is open Tuesday through Saturday, from 7:30am to 1:30 pm, then 3:30 to 7:30pm.