Sacramento To Las Vegas
Bakersfield has Woolgrowers and Noriega's, both Baque restaurants. I've been to Woolgrowners and liked it.
Murray Family Farms has a fruit stand near Arvin right outside of Bakersfield. It's on a road that connects Highway 99 and Interstate 5. I think it's one of the better in California. The selection isn't great, but what they do have is really fresh. I'd buy stuff for the rest of the trip.
Just to clarify the location of Murray Farms:
Their main location is on CA-58 about 18 or so miles east of the CA-99/CA-58 interchange in Bakersfield. It's on General Beale Rd. This location is a bit closer to Arvin & it's pretty obvious from the freeway. I've never stopped here so I can't say anything about the quality.
According to their web site, they have a 2nd location on Copus Rd., which does run between I-5 & CA-99 a ways south of Bakersfield (not too far north of the Grapevine). It's not along the route to Vegas if you're coming south on CA-99 & then heading east on CA-58.