Mostaza is a craft shop located on Carrer dels Carders in the Born neighborhood. It sells handmade items and gifts created by local artists—ranging from mugs and notebooks to T-shirts, illustrations, and decorative objects. The shop opened in November 2021 with the goal of connecting local creators with the public year-round, rather than just during occasional markets. It exclusively features handmade pieces by professionals produced in small batches, with a strong focus on local sourcing: nearly all the creators are from Catalonia. The shop defines itself as a neighborhood establishment designed for locals; for this reason, it has never sold any products featuring the word “Barcelona.” Every three to four months, it hosts gatherings for artists, and each December, it organizes the Mostaza Festival—a craft fair.