A miniature (palm-sized) version of butternut squash with a concentrated sweet flavor.
Honeynuts have an intense natural sweetness that becomes rich, caramel-y, and almost malt-like when roasted at high heat, they don't have to be peeled because they have thin skin (similar to a delicata), and they have have three times the amount of beta-carotene packed in. Its exterior is a deep honey color, and that—in addition to its inherent sweetness—is why it was named Honeynut. (source)