Root Vegetable Gratin

A luxurious layered gratin featuring tender sliced parsnips, celery root, sweet potatoes, and russet potatoes in a creamy sauce flavored with garlic, nutmeg, and black pepper. Perfect as a comforting side dish.

8 servings

1 hr 40 min

Published October 4, 2025

Ingredients

•1 lb parsnips (about 4 medium)
•1 medium celery root
•1 lb sweet potatoes
•1½ lb russet potatoes
•2 teaspoons salt
•1 teaspoon garlic
•½ teaspoon black pepper
•¼ teaspoon nutmeg
•½ cup chicken broth
•1⅞ cups heavy cream
•equipment

Cooking Instructions

1.
Put oven rack in upper third of oven and preheat oven to 400°F.
10 min
2.
Peel parsnips and cut crosswise into 3-inch lengths with a knife, then cut lengthwise around core into 1/8-inch-thick slices with slicer (discard core). Transfer to a large bowl.
15 min
3.
Peel celery root and all potatoes (prepare russet potatoes last to avoid discoloration) and halve lengthwise, then cut crosswise into 1/8-inch-thick slices with slicer. Add to parsnips along with salt, garlic, pepper, nutmeg, broth, and 1 3/4 cups cream, tossing to combine. Transfer to gratin dish, spreading evenly.
20 min
4.
Cut out a piece of parchment or wax paper to fit just inside gratin dish, then butter 1 side of parchment. Cover vegetables directly with parchment, buttered side down, then put dish in a shallow baking pan (to catch any drips). Bake until gratin is bubbling all over and vegetables are tender when pierced with a knife, about 50 minutes. Discard parchment.
50 min
5.
Just before serving, preheat broiler. Drizzle top of gratin with remaining 2 tablespoons cream and broil 4 to 6 inches from heat until browned, 2 to 3 minutes.
5 min

Cooking Instructions

Put oven rack in upper third of oven and preheat oven to 400°F.

10 min

Peel parsnips and cut crosswise into 3-inch lengths with a knife, then cut lengthwise around core into 1/8-inch-thick slices with slicer (discard core). Transfer to a large bowl.

15 min

Peel celery root and all potatoes (prepare russet potatoes last to avoid discoloration) and halve lengthwise, then cut crosswise into 1/8-inch-thick slices with slicer. Add to parsnips along with salt, garlic, pepper, nutmeg, broth, and 1 3/4 cups cream, tossing to combine. Transfer to gratin dish, spreading evenly.

20 min

Cut out a piece of parchment or wax paper to fit just inside gratin dish, then butter 1 side of parchment. Cover vegetables directly with parchment, buttered side down, then put dish in a shallow baking pan (to catch any drips). Bake until gratin is bubbling all over and vegetables are tender when pierced with a knife, about 50 minutes. Discard parchment.

50 min

Just before serving, preheat broiler. Drizzle top of gratin with remaining 2 tablespoons cream and broil 4 to 6 inches from heat until browned, 2 to 3 minutes.

5 min