florets, slice stems ẳ inch thick Celery Peel and cut into ẵ-inch chunks 20 minutes Celery Root (celeriac) Peel and cut into ½-inch chunks 20 minutes Jicama Peel and cut into ½-inch chunks 20 minutes Kohlrabi Peel and cut into 20 minutes ½-inch chunks Leek Thinly slice or dice 20 minutes Onion Thinly slice or dice 20 minutes Parsnip Peel and cut into ½-inch chunks 20 minutes Potato Peel and cut into ½-inch chunks 20 minutes Radish Cut into 20 minutes