Levadura Madre

This place is not exactly made for brunch, but it is probably the place with the best bread in Madrid, and therefore their toasts are one of the best you will find in this city.
In addition to that, they also offer croissants, cakes, muffins, artisan empanadas, etc., and very good coffee.
In their store, besides regular breads, you can buy corn bread, beet bread, cheese bread, rye honey and nuts bread, etc. Just be careful, because not all of their stores offer breakfast. We went to have breakfast at the one in San Joaquin Street, 4.