Grape-Nuts is a breakfast cereal created by Post in 1897. Per their website,

Grape-Nuts actually contains neither grapes nor nuts. It’s made from wheat and barley. So, why is it called Grape-Nuts? As with many great emblems in history, there are two versions of the story. One says that Mr. Post believed glucose, which he called “grape sugar,” formed during the baking process. This, combined with the nutty flavor of the cereal, is said to have inspired its name. Another explanation claims that the cereal got its name from its resemblance to grape seeds, or grape “nuts.”

Grape-Nut ice cream is vanilla ice cream with Grape-Nuts in it, simple and inspired, popular in New England but sadly unappreciated in much of the wider world. I got some last weekend at Peaceful Meadows in Plymouth. It was good.