Honestly, I wish it was more of a staple if anything. It's surprisingly hard to find really good Sichuanese food. I've had mapo tofu that ends up tasting more like a poorly done Hunan dish because of an unpleasant sourness and thickened sauce, even in restaurants that claim to be Sichuanese.
By far though, one of the best Sichaunese dishes which is unfortunately (and surprisingly) overlooked is their whitefish. If you know you know.
Tei Feng. The best.
Milwaukee does it proper. Szechuan Restaurant on National.
There's an extremely good/authentic Sichuan restaurant in one of the more boring parts of the SF Peninsula (Millbrae) called Yummy Szechuan.