Do you need specific classes (like Accounting or Business credits) or just anything? Is cost or time a bigger issue?
For accounting (and/or business), I'd recommend Louisiana State University: https://is.lsu.edu/courselist.asp?cat=Accounting&nid=102&pg= Fully accredited, I used them for all of my accounting classes, and they transferred seamlessly to KY CPA board. Their classes through their online format are at least 8 weeks in length, but you can do the everything except for the final exam whenever you want to, so if you were wanting it more accelerated (like 4 weeks), you could register for 2, do one (except final) in 4 weeks, do the other in the last 4 weeks, and then take the finals in the 8th week. Their “web enabled” courses don't have a specific length, but only allow you to submit 3 homework assignments per 7 days, so for say the “Fraud Auditing and Forensic Accounting”, you could do 14 lessons in about 5 weeks…but they don't send the final till they receive the last homework assignment, and the “web enabled” have paper exams, so you'd have to wait a couple more weeks before you'd have taken the final and have a final grade (the “online” ones have web-based finals, so instant grade). $505 per 3-credit course.
For quickest-credits, any-topic, cost-irrelevant, I'd recommend CLEP, DSST, and/or FEMA. I've got more info about these here: https://www.another71.com/cpa-exam-forum/topic/north-carolina-exam-app-denied-contest#post-355190 and then follow-up to that post here: https://www.another71.com/cpa-exam-forum/topic/cheap-college-credits-from-san-jose-state-150-per-online-class (Figured linking the threads would have other people's questions and answers, too, and maybe give you a fuller picture!)
Obviously I've worked with KY CPA board, not Cal, but as far as I'm aware, Cal accepts any accredited credits. LSU is accredited, and the CLEP, DSST, and FEMA options are all transferred to an accredited school and at that point become accredited, so these should all satisfy Cal too.
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