The authors have identified starch grains belonging to wild plants on the surface of a stone from the Gravettian hunter-gatherer campsite of Bilancino (Florence, Italy), dated to around 25000bp. The stone can be seen as a grindstone and the starch has been extracted from locally growing edible plants. This evidence can be claimed as implying the making of flour – and presumably some kind of bread – some 15 millennia before the local ‘agricultural revolution’.