Seattle doesn’t have many Brazilian restaurants or eateries, but there are two I can suggest.
If you are looking for churrascaria, the typical Brazilian steakhouse all-you-can-eat concept, Novilhos is a good choice. It’s a new place in Bellevue that I visited last winter.
Good selection of meats and a good buffet with side dishes, pastas, salads, etc. Still nothing compared to a churrascaria in Brazil (those who have experienced that will know), but authentic enough–the meat is of good quality and fresh.
The other place that many Brazilians like is Tempero do Brasil, located on University Way. It’s the place Brazilians living in Seattle consider most authentic, with dishes like feijoada, moqueca, and bobó being very good representations of Brazilian cuisine.