Yes, there is good Kao Soy in Norcal. Lynn's Thai in Cotati, in Sonoma County, offers excellent Kao Soy. Creamy, noodly, spicy deliciousness. Lynn's husband Lim, who is the chef, is from Chaing Mai, and his version, like everything on the menu, is made fresh with good ingredients. I have never had a bad dish there. Try the Pad Thai and Rolls of paradise too. There are other dishes from Northern Thailand on the menu as well.