Mashed turnips and potatoes

My SO and I have recently discovered the tastiness of the underappreciated turnip. Last night we made some mashed turnips and potatoes based on a recipe from Joy of Cooking (our all-time favorite cookbook). They turned out great, so I thought I'd post them up as my end-of-the-week recipe blogging post.

For those of you who aren't initiated into the cult of the turnip, it's a root vegetable from the cabbage family. Turnips are firmer than potatoes, similar to broccoli stalk or kohlrabi (which makes sense since they're all in genus Brassica). Turnips have a pleasant, mildly peppery taste (with a hint of sweetness) that mellows upon cooking. If you're looking for something new for Thanksgiving dinner, this dish could make a lighter, more vegetable-y alternative to traditional mashed potatoes.

All ingredient amounts are somewhat flexible (note that some ingredients are listed twice).

2 1/4 pounds turnips, peeled (and quartered, if large)
1 1/2 pounds potatoes, peeled (and halved or quartered if large)
1 1/2 cups chicken stock
4 tablespoons butter
1/2 teaspoon table salt
1/4 teaspoon freshly ground black pepper
2-3 scallions, finely chopped
Ingredients to add to the mashed potatoes - we used some butter (~2 tablespoons), cream (~2 tablespoons, or milk), sour cream (~2 tablespoons), and salt (to taste, maybe 1/2 teaspoon?)
2 tablespoons fresh parsley, chopped

1. Add the turnips to a pot of boiling water and boil for 6 minutes.
2. Meanwhile, add the chicken stock to another pan and bring to a boil, then add 4 tablespoons butter, 1/2 teaspoon salt, and 1/4 teaspoon ground black pepper, stirring to mix.
3. Remove the turnips from the boiling water (save the boiling water to cook the potatoes in) and add them to the chicken stock pan (the turnips should be mostly covered). Simmer, covered, until the turnips are nearly tender throughout (~10-20 minutes).
4. Meanwhile, add the potatoes to the pot of boiling water and cook them until tender throughout (~15-30 minutes depending on the size of the pieces).
5. When the turnips are close to done (we just approximated), add the scallions to the turnip mixture and simmer for a few minutes more (until the scallions are cooked and the turnips are completely tender).
6. When the turnips are done, remove them from the cooking liquid. Reduce the cooking liquid until it is reasonably thick (a few minutes of boiling).
7. Puree the turnips with the reduced cooking liquid until smooth; we used our Cuisinart food processor. (We also added a bit more butter here, but it's probably not needed.)
8. Mash the potatoes with their ingredients (butter, cream, sour cream, and salt, or whatever you desire) in a large bowl.
9. Fold the turnips into the mashed potatoes, add parsley, and serve.

Rombauer, I. S., M. R. Becker, and E. Becker. 1997. Joy of Cooking. Scribner, NY.

[Update: A reader named John added the following in the comments: "In Scotland where turnips are known as swedes or neeps this mixture is called Clapshot and is often associated with the Orkney Islands."]