In this article, the authors describe a varied day of stimulating mathematics with key stage 2 learners--all revolving around chocolate. They used a variety of stimuli organized around the chocolate theme. A whole day was spent on using and applying mathematics, and the exercise proved to be enjoyable for both staff and pupils. The children reasoned, communicated, analysed, checked, organised, hypothesised, explained and made decisions about their work, with minimum input other than the stimuli. The experience confirmed that days organised for pupils and adults with a shared passion for mathematics give enormous pleasure and satisfaction to those involved; that pupils enjoy an opportunity to talk about their mathematics; and that accessible problems without "answers" provide wonderful learning opportunities for those who think beyond the problem. (Contains 2 figures.)