Food waste represents an inefficiency along the supply chain that can hamper food system productivity. As countries align national targets with the United Nations’ Sustainable Development Goal to halve per capita food waste at the retail and consumer, addressing consumer food waste is regarded as one of the key channels to achieve these goals in developed countries. Acquisition of knowledge, such as organizational learning-by-doing, has been shown to be a significant source of productivity growth in a variety of industries. This paper investigates the role of incidental learning in reducing consumer plate waste during all eating occasions over approximately one week based on a unique data source with food-item level data collected from 50 adults from the United States using the Remote Food Photography Method.® Aligning with existing literature, we find subject behavior is consistent with significant incidental learning. As observed plate waste experience accumulates, subjects accomplished significant plate waste reduction by cleaning their plates, which also increased calorie intake. No evidence is found that learning from the past alters the amount of food that subjects’ select. Given that habitual plate cleaning has been associated with overweight and obesity, social welfare maximizing public policy interventions should consider explicit information to help consumers switch the focus from the intentions not to waste (i.e., minimize food waste by cleaning plate after food was over-selected) to improvements in the ability to reduce food waste (i.e., selecting an appropriate amount of food).