Was Proust Inspired by Madeleines?

Madeleine is perhaps the most famous cookie in the history of literature. It's the taste of madeleine dipped in tea, on a Sunday morning, that sets Proust's vast novel of remembering the past in motion. But it seems now that perhaps Proust was not so honest with his description of the cookie. An article in Slate lends weight to the blasphemous thought (at least to the Proustians) that Proust's madeleines may never have existed at all and it seems that he made it all up and served it in prose so beautiful and authentic that no-one ever doubted it. This is from the sidebar of the article:

Joshua Landy, who may be the field's leading madeleine debunker, subjects the Cookie Question to an unflinching investigation in his recent book, Philosophy as Fiction: Self Deception and Knowledge in Proust. He reports that, in all of Proust's 20 volumes of correspondence, there is no mention of an "enchanted encounter with baked goods." Not only was there no madeleine, there probably was no piece of toast either. Some scholars have assumed that the toast-dipping scene in an early version of Remembrance called Against Sainte-Beuve is based on an actual experience. But Against Sainte-Beuve, Landy sensibly argues, isn't evidence of anything—it's fiction. For all we know, he quips, Proust had an epiphany with a Danish.

Proust biographer William Carter concurs that there's no evidence Proust's work was inspired by any baked good. But he points to a December 1898 letter as the earliest dated instance in which Proust describes an involuntary memory experience. In it, the scent of tea and mimosa evokes Christmases past. This may have been the true genesis of the madeleine scene.

For those unfortunate souls who have no idea what the fuss is all about, here is a link to the madeleine scene from the novel.