Here's his bio and some quotes from his website:
Les Blank is a renowned independent filmmaker, whose poetic work offers intimate, idiosyncratic glimpses into the lives, culture, and music of passionate people at the periphery of American society. Topics have included Cajun, Mexican, Polish, Hawaiian, and Serbian-American music and food traditions, Afro-Cuban drummers, Texas bluesmen, Appalachian fiddlers, flower children, garlic, and gap-toothed women.
Blank is perhaps best known for his feature-length “Burden of Dreams” (1982), documenting the chaotic production of Werner Herzog’s 1982 film “Fitzcarraldo” in the jungles of South America. Honored with a Criterion DVD edition and winner of the British Academy Award, Ebert called the film “one of the most remarkable documentaries ever made about the making of a movie.”
Another of Blank’s best-loved works is “Garlic Is As Good As Ten Mothers” (1980), a seminal food film featuring culinary pioneer Alice Waters and the Gilroy Garlic Festival. The film, notorious for its mouthwateringness, is traditionally shown in “Aromaround,” with garlic simultaneously roasted in-theater.
Blank’s most recent film, “All In This Tea” (2007), is a feature documentary following tea specialist David Lee Hoffman to the most remote regions of China in search of the perfect leaf. Hoffman single-handedly opens the government’s eyes to the value of their own tradition, ensuring the survival of small, artisanal growers (“. . .a delicious documentary!” –The New York Times; “. . .an entertaining portrait of an eccentric figure whose singular passion proves infectious.” – Hollywood Reporter).
“I can’t believe that anyone interested in movies or America…could watch Blank’s work without feeling they’d been granted a casual, soft-spoken revelation.” - Time Magazine
“Blank is a documentarian of folk cultures who transforms anthropology into art.” – New York Times (John Rockwell)
“A master of movies about the American idiom… one of our most original filmmakers.”- New York Times (Vincent Canby)