Lightly seasoned: "Diana Kennedy: Nothing Fancy"

Some films threaten to review themselves. The documentary Nothing Fancy is an affectionate, no-frills 83 minutes spent in the company of Diana Kennedy, the Englishwoman who helped bring home the joys of Mexican cuisine to North America in a series of bestselling cookbooks and primetime TV series. (These latter are excerpted here, and it would be a hard-hearted viewer who didn't delight in the cheeringly naff sight of Kennedy using red peppers as earrings during one such show's opening credits.) Now located deep in rural Mexico, where she lives alone, driving a Nissan truck to and from the local markets, Kennedy emerges as a recognisable type: an upper-class eccentric who became an expert in what was considered a highly niche field, a woman possessed of both the curiosity and time to hoover up decades of culinary knowledge passed down from one generation to the next, yet who also enjoyed an access to publishing houses and television networks most Latin-American chefs wouldn't have had in the 1970s. Director Elizabeth Carroll fair revels in that eccentricity. Here is Kennedy taking a half-hour to make coffee for her visitors because she insists on personally roasting the beans rather than reaching for the Nescafé; here she is getting disproportionately huffy while whipping up some guacamole ("I'm so sick of all this saltless cooking!"). You can see why a filmmaker might be drawn to such a personality; once there, though, I'm not sure Carroll finds much of a story to tell.

I knew nothing about Kennedy (and scarcely more about Mexican cuisine) going in, so the first half served as a useful historical briefing, but increasingly the experience of Nothing Fancy becomes that of watching a 21st century documentary rather dutifully ticking off everything a 21st century documentary is meant to do, in the absence of any greater vision or insight. Carroll is careful to counterbalance her white European subject with testimony from indigenous Latin voices; she makes a case for Kennedy as some form of feminist figurehead; and as the film progresses, Kennedy is allowed to editorialise about consumption and sustainability in a way that chimes with the charity work we see her performing, presumably a trade-off of sorts for the access she grants Carroll and her crew. That's all fine and dandy, but the second half contains a lot of superfluous filler material, artlessly stuffed in to counter the fact Kennedy has undergone no great dramas for the film to speak of, and broadly seems comfortable indeed with her lot, saltless cooking aside. You could, at a push, argue it underlines the subject's credentials as an entirely independent domestic goddess, but is there a compelling cinematic reason for us to wind up watching Kennedy peg her washing out? (Here, as elsewhere, we spy the pernicious influence of reality TV on modern documentary: nowadays just about anything, however banal, counts as content.) No denying that Kennedy, just turned 97, remains a lively character, but Carroll's film can't make the substantive case for her life's work that, say, a box set of her TV shows or cookbooks doubtless could. Dare I say it: it needed a dash more spice.

Diana Kennedy: Nothing Fancy will be available to stream from Friday.