Description

A cozy, crowd-pleasing Thanksgiving side dish featuring layers of sweet potatoes, parsnips, rutabaga, and carrots baked with Gruyère and cheddar cheese in a creamy sauce, topped with a crispy breadcrumb crust. Perfect for festive gatherings or comforting family dinners.

Ingredients

Scale

2 large sweet potatoes, peeled and thinly sliced (about 1 pound)
2 medium parsnips, peeled and thinly sliced (about 8 ounces)
1 medium rutabaga, peeled and thinly sliced (about 12 ounces)
2 large carrots, peeled and thinly sliced (about 6 ounces)
1 small yellow onion, thinly sliced
2 cloves garlic, minced
1 1/2 cups shredded Gruyère cheese (about 5 ounces)
1 cup shredded sharp cheddar cheese (about 4 ounces)
2 cups heavy cream
2 tablespoons unsalted butter, melted
1 teaspoon fresh thyme leaves (or 1/2 teaspoon dried thyme)
1/2 teaspoon ground nutmeg (optional)
Salt and black pepper to taste
For the Topping:
1/2 cup panko breadcrumbs (or gluten-free crumbs)
2 tablespoons grated Parmesan cheese
1 tablespoon unsalted butter, melted

Instructions

Preheat oven to 375°F (190°C). Grease a 9×13 inch baking dish with butter.
Using a mandoline or sharp knife, slice sweet potatoes, parsnips, rutabaga, and carrots into 1/8-inch rounds. Place in a large mixing bowl. Add thinly sliced onion.
Sprinkle veggies with 1 teaspoon salt, 1/2 teaspoon black pepper, and thyme leaves. Toss to coat evenly. Let sit for 5-10 minutes to draw out excess moisture.
Arrange half the veggie slices in the prepared baking dish, overlapping slightly. Sprinkle with half the garlic, half the Gruyère, and half the cheddar. Repeat with remaining veggies, garlic, and cheeses. Pour melted butter evenly over the layers.
Pour heavy cream slowly over the entire dish, letting it seep into all the nooks. Sprinkle with nutmeg if using.
Cover dish loosely with foil. Bake for 40 minutes until veggies begin to soften and cream bubbles.
While baking, mix panko breadcrumbs, Parmesan, and melted butter in a small bowl.
Remove foil. Sprinkle breadcrumb mixture evenly over the gratin. Return to oven and bake uncovered for another 20-25 minutes, until top is golden brown and veggies are tender.
Let gratin sit for 10 minutes before slicing to allow creamy layers to set.

Notes

For gluten-free, use almond flour or gluten-free breadcrumbs for the topping. Slice veggies evenly for best texture. Salt veggies before layering to prevent sogginess. Let gratin rest after baking for easier slicing. Can be made ahead and reheated. Swap cheeses or root veggies as desired.

Prep Time: 20 minutes
Cook Time: 60 minutes
Category: Side Dish
Cuisine: American

Nutrition

Serving Size: 1/10 of recipe (about 1 cup)
Calories: 310
Sugar: 8
Sodium: 420
Fat: 18
Saturated Fat: 11
Carbohydrates: 28
Fiber: 5
Protein: 10

Keywords: Thanksgiving, gratin, root vegetables, cheesy, side dish, vegetarian, comfort food, holiday, casserole