1. Preheat oven to 400.
2. Cook diced parsnips in simmering water until just fork tender, then drain well.
3. Spray inside of baking dish with non-stick spray.
4. Put cooked parsnips in dish.
5. Pour butter over them then sprinkle with brown sugar and mustard.
6. Bake uncovered for 15 to 20 minutes, until they start to get golden.
Parsnips have a bad reputation for being just a tad bitter. I have to agree that if you just boil them and eat them, they might not be that appealing to some people. That's why most recipes for parsnip side dishes have added sugar and other seasonings, like mustard, just to relieve them of their slight bitterness.
If you haven't tried parsnips yet, you should. Parsnips are a great value for the few pennies they cost. They are loaded with fiber, folic acid, calcium, and potassium. Also a good source of several B vitamins, vitamin C, iron, and zinc. Cook up a batch and I'm guessing you'll have to agree they are more pleasing than you first thought.