Longman Dictionary of Contemporary English
Wiktionary
n. 1 Simple, home-cooked-style food associated with one's formative years, often a staple of diners and other informal restaurants. 2 Food consumed to feel comfort or alleviate stress rather than to receive nutrition.
WordNet
n. food that is simply prepared and gives a sense of wellbeing; typically food with a high sugar or carbohydrate content that is associated with childhood or with home cooking
Wikipedia
Comfort Food: A Novel by Noah Ashenhurst contains a cast of characters: a romantic academic, a self-assured young writer, an enigmatic musician, a slacker, a wealthy mountaineer, and a former heroin addict—characters whose lives intersect in the unique, award-winning debut novel.
Usage examples of "comfort food".
The pastries displayed in the glass case were comfort food at its purestreminders of the days when calories and cholesterol didn't count.
Still rattled from the adventure and the subsequent shake-up, it didn't want anything as heavy as comfort food.
Shep wasn't currently able to cope in public, however, and when in this condition, he refused to eat anything but comfort food with a high fat content.