Ummul Mu'mineen Hazrat Aishah radiyallahu anha says, Rasoolullah sallallahu alaihe wasallam used to come to me and ask if there was any food available. When I would say, "No," he would say, "I have intended to fast."Once when Rasoolullah sallallahu alaihe wasallam came and enquired, I replied, 'We have received a present.' Rasoolullah sallallahu alaihe wasallam asked, 'What is it?' I replied, 'Malidah (a type of cake made of dates, ghee, cheese or flour).' He said, 'I had made an intention of fasting already.' He then ate some from it. (ES)
English reference (ES): Book 25, Hadith 173 (ES)
Arabic reference (ES): Book 26, Hadith 182 (ES)