Ye Gods, this is a task. I got back from California two months ago, and I can’t remember a thing. I’ve got a stack of menus here an inch thick, detailing two dozen meals in more than 20 restaurants (including two or three of the best in the world), costing a total of around $3,000, and all I can really remember is the weather (lovely, thank you).

Was it like this for Christopher Columbus? Did he get back from his famous journey in 1493 and remember only that you could eat lunch outside in a T-shirt even in winter? Did he keep meaning to write up his experiences in detail but only finally got around to it after two months, and then couldn’t remember much except that he had found some new continent with, like, turkeys running around, and brown people who looked a bit like Indians, and really friendly service?

Did he get most of his memories organised into some sort of a narrative and then his girlfriend looked over his shoulder at what he had done so far and said, “Aren’t you going to put in about the fags and the potatoes?”

Memory itself, the power of recall, is supposed to be a great filter of experiences. You’re supposed to remember only the really important stuff. Often, when I’m writing up a restaurant a couple of days after the meal and I can’t remember, say, the second pudding, or how they did the cabbage, then I say to myself, “Hey ho, if I can’t remember then I guess it wasn’t all that memorable,” and move on to what I can remember, which is most often the shape of the waitresses, or something witty I said about artichokes.

But the filter is playing strange tricks on me this time. For example, the main reason I went to California was to have dinner at the French Laundry, which was voted best restaurant in the world two years running in 2003 and 2004 and is a close runner-up to El Bulli in the survey in most other years. But none of the 20-odd dishes I ate there (which I may, if you’re good, come back to next week) has stuck in my mind half as well as the burger I had at In-N-Out, when I pulled off the Interstate to get petrol on the way there, or the not-especially-good “breakfast burrito” I had just after dawn the next morning, following a balloon ride down the Napa Valley.

Man, that was a good burger. In-N-Out is a local, reportedly Mormon-owned chain that operates out of California (and into Nevada, Arizona and Utah) and offers only three choices: hamburger, cheeseburger, and the “double-double”. It’s as clean, rapid and slick as McDonald’s, but the burgers are more evidently handmade, the patties plump and brown and shiny, and each one half-bundled in a greaseproof napkin so that its bright salad and ochre cheese bulge and yabber at the presented edge. The taste is deep and sexy, and the chips are cut from potatoes. It’s been going since 1948, seven years longer than McDonald’s, and the fact that it still caters only to four states, while McDonald’s has taken over the world, is proof, if proof were needed, that the market is bunk.

I could go on, once we’re chomping on burgers and chatting of this and that, to tell you about Taylor’s Automatic Refresher – a St Helena roadside burger joint founded a year later in 1949 – where the burgers were better still, weepily, dreamily wonderful, like nothing you can get over here, and the chips were home-cut with the skins on, tasting of root and wood and fire and vitamin C.

But then there would be no room for Chez Panisse, in Berkeley’s “Gourmet Ghetto”, home of Alice Waters and the Californian natural food revolution of the Seventies, where I sat in slatted sunlight in a little balconied afterthought at the back of the first-floor brasserie and had by some way the best (oiliest, nuttiest) avocado I have ever known, with easily the best heirloom tomatoes (waterless, meaty), all on wafer-thin, crisp, toasted sourdough, and then a thin pizzetta with a soft egg, grated bottarga and scallions, and a fat piece of fried chicken on the smoothest borlotti beans, and halibut with whole new incarnations of cauliflower, leeks and romanesco broccoli, all washed down with cool tap water from an engraved glass jug. All of which I remember quite vividly, but not as vividly as the car I hired to get there.

It was a red Ford Mustang convertible with a noise under the bonnet like King Kong shouting to be heard over the roar of a waterfall. It’s not the car the Mustang used to be, of course – it’s a pretty charmless, plasticky, almost embarrassed modern approximation – but still had enough, when I opened her up on Route 1 heading out to Big Sur, to get me pulled over almost immediately (“Remain in the vehicle, sir. Remain in the vehicle! With your hands where I can see them. Licence, insurance, passport…”), fined, and slapped with a big yellow ticket.

Back in San Francisco, we went to the Slanted Door (most talked-about Vietnamese on the West Coast), Sushi Groove (where they play hip tunes to distract you from the occasionally iffy fish), MarketBar (our first meal, jet-lagged, four in the morning, Anchor Steam beer and grilled mahi mahi), Scoma’s (one of a thousand upmarket crab shacks on the waterfront where a million Californians trawl for shellfish deals), and a number of other widely vaunted joints. But they don’t stick in my head like the homeless woman in a wheelchair I saw on my way back from a midnight movie, eating a donated half-sandwich and crying between mouthfuls.

San Francisco is full of homeless. Super-saturated, so that they spill out all over the floor. Mostly schizophrenics from the look of it. Ten to a street corner. Overlooked by the food revolution.

We went to Chinatown, where Chinese hordes as old as the state of California itself farm unfathomable mountains of multicoloured ethnic tat and glittering Orientalia in flea markets the size of middling market towns. We ate dim sum at City View, one of the many places touted as the best around, and found top-rate trolleyed dumplings – probably one level above the best that are wheeled around London dim sum canteens, but a level below Royal China.

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