Gold Potato & Root Vegetable Gratin

Root Vegie Gratin.jpg

Tired of your same old green bean casserole. Tired of trying to revamp it to meet today’s lighter diets without much success. Here’s a new casserole I’ve adapted from Cook’s Illustrated that is absolutely delicious and ideal for Thanksgiving, whether you are hosting in your home or toting a dish to someone else’s. The veggies may not be green, but they are packed with nutritive value and loaded with vitamins.

About slicing
Unless you’re a masterhand (my word :), a mandolin is a necessity when making this. Because celery root and rutabagas are so tough and heavy, unless you quarter them, even a mandolin won’t slice them. A cheap plastic mandolin like mine, however, does a fine job as long as they are quartered.

Why add wine?
Adding wine to a gratin is unique, but it plays an important role, besides brightening the flavor of the veggies.. Its acidity strengthens the pectin in the potatoes so that they remain intact while the denser, less-starchy rutabaga and celery root cook through. Straight from Cook’s Illustrated, here’s how it works: Potato cells have an abundance of starch granules; when these granules swell with water during cooking, they press against the cell walls, eventually causing them to burst and release starch. But when potatoes cook in water with wine, the wine lowers the pH, which strengthens the pectin in and around the cell walls, helping them resist bursting. The upshot is a pliable, not mushy, potato.

I seldom have a bottle of dry white wine open, so I go by Julia Child’s trick and substitute dry white vermouth, imported preferred. I always have a bottle of it in my fridge for cooking.

To help the top layers of the gratin cook through at the same rate, cover it for the first portion of the cooking time. A layer of Parmesan-enhanced panko bread crumbs added after the foil is removed toasts while the gratin finishes cooking, adding a crispy, golden crust that is nutty and cheesy in flavor.

Don’t think twice about making it a day ahead. It is equally as delicious heated up the next day.

If you are still deciding on your Thanksgiving menu, give this tasty casserole a try. I know that once my family tastes it, it is going to become a new favorite.

Wishing you all a very Happy Thanksgiving. In the midst of these chaotic times, when we sit around the table with our family and loved ones, we are reminded of all that we have to be thankful for. Along with my family, I am grateful to all of you for being here and giving me so much joy.

1 tablespoon plus 1 ½ cups water
1 ½ teaspoons Dijon mustard
2 teaspoons all-purpose flour
2/3 cup dry white wine
½ cup heavy cream
½ onion, chopped fine
1 ½ teaspoons minced fresh thyme
1 garlic clove, minced
2 pounds Yukon Gold potatoes, peeled and sliced 1/8 inch thick
1 large celery root (1 pound) peeled, quartered and sliced 1/8 inch thick
1 pound rutabaga, peeled, quartered and sliced 1/8-inch thick
¾ cup panko bread crumbs
¾ cup grated Parmesan cheese
4 tablespoons butter, melted and cooled

 1Adjust oven rack to middle position and heat oven to 375 degrees. Grease 13 by 9-inch baking dish. Whisk 1 tablespoon water, mustard, flour, and 1 1/2 teaspoons salt in medium bowl until smooth. Add wine, cream, and remaining 1 1/2 cups water; whisk to combine. Combine onion, thyme, garlic, and 1/4 teaspoon pepper in second bowl.

2Layer half of potatoes in prepared dish, arranging so they form even thickness. Sprinkle half of onion mixture evenly over potatoes. Arrange celery root and rutabaga slices in even layer over onions. Sprinkle remaining onion mixture over celery root and rutabaga. Layer remaining potatoes over onions. Slowly pour water mixture over vegetables. Using rubber spatula, gently press down on vegetables to create even, compact layer. Cover tightly with aluminum foil and put on a tray, in case there are any drips.

3. Bake for 50 minutes. Remove foil and continue to bake until knife inserted into center of gratin meets no resistance, 20 to 25 minutes

4While gratin bakes, combine panko, Parmesan, and butter in bowl and season with salt and pepper to taste. Remove gratin from oven and sprinkle evenly with panko mixture. Continue to bake until panko is golden brown, 15 to 20 minutes longer. Remove gratin from oven and let stand for 25 minutes. Cut into squares to serve.

To make ahead: Gratin may be refrigerated overnight. Bring to room temperature and reheat uncovered at 375 degrees for 30 minutes or until heated through. It may be even better when reheated.

Makes  8 to 12 servings.


Print Friendly and PDF