The greenhouse gases arising from food account for more than ten percent of the UK carbon footprint. Carbon-related food interventions such as smartphone apps have largely targeted supermarket shopper decisions 'in store' and have yet shown little evidence of impact. To be truly relevant, we must seek nuanced understandings of food acquisition both within and beyond the supermarket: these include the negotiation and planning of household meals, and positioning with respect to take-away and convenience foods. Using multidisciplinary methods as diverse as ethnographic observation, interaction design, carbon profiling and crowdsourcing, we will iteratively develop and trial both low and high tech interventions which meaningfully support food acquisition and carbon awareness, with the aim of promoting lower impact food practice. Built into the research programme is continual engagement with the supermarket itself, to explore opportunities for making scalable, sustained reductions, in its role as a food institution for tens of thousands.