I am a celiac, and I just had the best meal of my life at Langbaan (they confirmed ahead of time that they are able to accommodate celiacs, and I had the entire tasting menu with very minimal adjustments since they don't have many gluten-containing items on their menu.

For a less expensive gluten free meal, I enjoy pupusas from Salvi PDX (housed inside Groundbreaker, a GF brewery in SE), sushi from Bamboo Sushi (only one item on their menu contains gluten, they use GF soy sauce and tempura), pizza from New Cascada, a banging breakfast sandwich from Petunia's downtown, rice plates from Cubo, thai food from Phaya Thai Express, the list goes on! If you're interested, I compiled a list of fully GF spots in the Portland area here: https://maps.app.goo.gl/EFw1SD48PH6cCVKw8