I visited the Chinjin Eastern House in Cupertino (or is it technically San Jose?) and can testify that this is a real-deal Chinese Muslim food restaurant.
Many excellent Chinese breads and other wheat cakes from the Northeast (most of the staff are from Tianjin) and a number of dishes from China's interior, such as the famous Xi'an style lamb stew.
Unfortunately the best items on their menu are only on the Chinese language menu and are not translated. I talked to the staff about this for awhile, and they are convinced that Americans don't want these things and don't want to see them on the menu.
To be fair, I didn't see any Chowhounds in the restaurant tonight; there were non-Chinese Muslims, who seemed to be eating Americanized Chinese food that happened to be halal, and Chinese people eating various authentic Northern Chinese dishes.
Although there are some authentic Chinese items scattered throughout the regular, translated menu, here's a full transcription, transliteration and translation of the Chinese language-only menu.
Let me also mention that there is excellent la4 jiang4 (chili paste) on the table and you can ask for terrific hei1 cu4 (black vinegar) to go with the breads. The scallion pancake was quite good -- thick and flavourful. The best thing I had was the beef shao bing --- thin sliced beef in a sesame covered flat bread. This is particularly good with some chili paste added. The xian4 bing3 (beef hamburger) was not to my liking --- a bit too oily for me. And the yang2 rou4 pao4 mo2 (lamb stew) was quite excellent. You are given a big bowl with a very dense, thick bread cake and you should rip it up into little shreds yourself. As soon as you do this, the bowl will be whisked back into the kitchen and the lamb stew added. This is a thick stew with pieces of lamb, thin noodles, and various vegetables, topped with cilantro and is a very common dish in Shaanxi province.
Anyway, here's the menu:
牛肉馅饼 - niu2 rou4 xian4 bing3 - beef "hamburger"
芝麻酱肉烧饼 - zhi1 ma jiang4 rou4 shao1 bing - thin sliced beef in flat sesame cake
葱油饼 - cong1 you2 bing3 - scallion pancake
芝麻大饼 - zhi1 ma da4 bing3 - sesame flat bread
黄鱼馅蒸饺 - huang2 yu2 xian4 zheng1 jiao3 - yellow fish stuffed steamed dumplings (8)
牛肉蒸饺 - niu2 rou4 zheng1 jiao3 - steamed beef dumplings (8)
素蒸饺 - su4 zheng1 jiao3 - steamed vegetable dumplings (8)
锅贴 - guo1 tie1 - fried potstickers (8)
牛肉小笼包 - niu2 rou4 xiao3 long2 bao1 - beef soup dumplings (8)
槓子头 - gang4 zi3 tou2 - dense bread cake
羊肉褡裢火烧 - yang2 rou4 da1 lian huo3 shao - long lamb filled wheat cake
考羊肉串 - kao3 yang2 rou4 chuar4 - roast lamb skewer
凉拌海带 - lian2 ban4 hai3 dai4 - cold kelp
滷水花生 - lu3 shui3 hua1 sheng1 - brined peanuts
泡菜 - pao4 cai4 - pickled vegetables
牛肉/羊肉泡馍 - niu2 rou4 / yang2 rou4 pao4 mo2 - beef or lamb stew with bread and cilantro