I may get my Swiss citizenship taken away for this, but my favorite is a place in nearby France (10 minutes by car) in St. Julien called La Table à Raclette:
http://maps.google.ch/maps/place?hl=...12680915320322
It's not touristy at all, in fact you get a lot of blue collar guys during the day. Not sure how it is in the evening. The do a lot of stuff besides raclette, but it's their specialty, they do in several varieties, and they do it well. Service is a little slow at times, but Monday evening you should be OK, just make sure it's open.