'Comfort Food' is food that gives emotional comfort and provides a nostalgic or sentimental feeling to the person eating it. It's usually prepared in a traditional way and reminds the person of her childhood, home, family and friends.
Example of use: Jessie –"Every time I get upset, I ask my husband to make me a big bowl of Grandma’s delicious creamy Mac & cheese and imagine myself sitting in her kitchen, with not a worry in the world." Emma –"Wow, that sounds like the perfect comfort food. The only thing my Grandmother could make was Apfelstrudel, and I hate apples."
The first known use of the term was in the 1966 May edition of the New York Times, in a book by Theodore Isaac Rubin, 'The thin book by a formerly fat Psychiatrist': "Think thin… lose weight… learn about ammunition foods, comfort foods, and emergency foods."