Parsnip Mashed Potatoes- Description It started with parsnips. Lately, it seems like every cooking show I watch, they’re doing something with parsnips. I’d never even heard of parsnips before last month, and now they’re everywhere. I suppose that’s how it always goes. So what is a parsnip? Parsnips are a root vegetable; they look like white carrots, only less sweet. So, I decided that for my first parsnip dish, I’d go with something I mastered long ago.