Cook the Book: Turnip and Potato Gratin

Cook the Book: Turnip and Potato Gratin

This week's Cook the Book entry, How to Pick a Peach by Russ Parsons, is all about where the foods in the produce aisle come from, when they're at their best, and how to pick a prime example of whatever it is you're in the market for. Today's recipe (or should I say, "this evening's recipe," as it's a little later than usual) again gives you something to look forward to, since, like yesterday's winter greens entry, it stars an ingredient that usually rolls around in winter--turnips. This Turnip and Potato Gratin makes good use of the root vegetables, so be sure to bookmark it for later. The recipe follows after the jump, but first a couple of tips from Parsons.

  • How to choose: Choose roots that are free from nicks and scars. Check the top of each turnip, where the greens once were. As the roots sit, they will continue to sprout new greens, which the produce manager will trim. The more the tops have been trimmed, the older the root probably is. In Japanese markets you can find small white turnips that have the tops attached. These are milder and sweeter than other turnips.
  • How to store: Store turnips in a plastic bag in the refrigerator.


  • 1 garlic clove, peeled
  • 6 turnips, peeled
  • 2 large boiling potatoes, peeled
  • 2 teaspoons salt
  • 1 1/2 cups heavy cream
  • 3 ounces Gruyère or Comte, grated or sliced


  1. 1.

    Heat the oven to 450 degrees. Rub the garlic clove allover the inside of a heavy gratin dish, then butter the dish well and set aside. Discard the garlic.

  2. 2.

    Slice the turnips and potatoes as thinly as you can, ideally using a mandoline or Japanese slicing tool. Toss the vegetables with the salt and place them in rough layers in the gratin dish. Don't worry about arranging them; you'll be stirring them later. Bake until softened, 20 to 30 minutes. Stir with a spatula every 10 minutes, making sure the bottom layer doesn't scorch.

  3. 3.

    Pour the cream over the potatoes; it should come just to the top layer without covering it. Distribute the cheese over the top and bake until the cream thickens and the top is browned, about 30 minutes. Serve hot.