Butternut Squash and Celery Root Gratin

Canadian Thanksgiving just passed, and Soli and I had a small Thanksgiving dinner at our house for some friends and family, It was just nine people, but we felt like we had to make a ton of food, and a ton of food we made!

This butternut squash and celery root gratin is one of the dishes I made. I had never actually cooked with celery root, so I was excited to give it a try. It is a pain to peel, but a delight to eat, so it all worked out in the end. I really, really liked this gratin. I adore the taste of celery root, and it really stands out in this dish. It’s definitely something a little bit different from the usual gratin. The butternut squash, as to be expected, is sweet and a perfect compliment to the celery root.

The streusel is awesome too. I added more of everything in the topping than the original recipe suggested and am happy I did. The thyme gives the gratin that Thanksgiving, warm, homey taste, and I find the parsley added some freshness. Using panko instead of bread crumbs is important, as panko is so much lighter and more crispy.

Butternut Squash and Celery Root Gratin

You’ll notice there’s no cheese in this…And the gratin doesn’t need it! The cream adds all the richness it needs, and there’s no need to mask the stars of the dish, the squash and celery root. A definite winning side!

(Oh, and I had made it a day ahead of time, baking it about 10 minutes short of the suggested time, then reheated it slowly, and covered, in the oven before dinner)

Butternut Squash and Celery Root Gratin

Butternut Squash and Celery Root Gratin with Walnut-Thyme Streusel
Adapted from Chow.com

WALNUT-THYME STREUSEL
1 ¼ cups panko
4 tablespoons unsalted butter (1/2 stick), melted
3/4 cup finely chopped walnuts
3 tablespoons finely chopped fresh Italian parsley
2 teaspoons fresh thyme leaves
1-2 teaspoons (or to taste) kosher salt

BUTTERNUT SQUASH AND CELERY ROOT GRATIN
1 1/2 cups heavy cream
1 medium butternut squash (about 3 pounds), peeled, cut in half, and seeded
1 medium celery root, also known as celeriac (about 1 pound), peeled and cut in half
2 tablespoons unsalted butter (1/4 stick), plus more for coating the baking dish
1 large white onion, thinly sliced
Salt
Freshly ground black pepper

STREUSEL
1. Combine all ingredients in a medium bowl and mix until the butter is incorporated. Cover and place in the refrigerator until ready to use.

GRATIN
1. Heat the oven to 400°F and arrange a rack in the middle. Coat a 13-by-9-inch baking dish with butter and set aside.

2. Pour the cream into a large bowl and set aside. Slice the squash and celery root into 1/4-inch-thick slices with a mandoline or sharp knife, placing the pieces in the cream as they are cut. Toss until well coated.

3. Melt the butter in a medium frying pan over medium heat. Add the onion and season well with salt and pepper. Sauté until soft and translucent, about 5 minutes; set aside.

4. Make the gratin by ladling a third of the squash–celery root mixture into the prepared baking dish, then seasoning well with salt and pepper. Top with half of the onions, then another layer of squash and celery root. Season the second layer with salt and pepper and cover with the remaining onions. Place the last of the squash and celery root on top and press down to create an even surface. Season with salt and pepper, then pour the remaining cream over top.

5. Sprinkle the streusel evenly over the gratin. Bake until the vegetables are soft and the streusel is golden brown, about 40 to 50 minutes. Let sit at room temperature for about 20 minutes before serving.