Root Vegetable Gratin Recipe

Iain Bagwell
30 Minutes
1 Hour, 40 Minutes


Serves 8 (serving size: 1 cup)

Assemble layers of veggies and bubbly cheese a day ahead to save on Turkey Day prep. Fall’s harvest brings with it plenty of fresh, seasonal vegetables that find their way to our dinner tables (in the South, this is usually in the form of countless vegetable casseroles). Pumpkins, Brussels sprouts, cabbage, squash, and cauliflower all star in their own hearty dishes; sometimes, these delicious and unique side dishes are the real stunners on the menu. This 6-ingredient root vegetable recipe is no exception. Perfect for those who want to bring big flavor without spending too much time in the kitchen, this heart-warming root vegetable casserole brings the best of fall flavor into your kitchen with a few, simple ingredients. Celebrate the season with this cozy, comforting side dish made from our favorite seasonal root vegetables—hearty russet potatoes, crunchy rutabagas, and snappy parsnips. Cooked in the au gratin style, a French culinary technique in which dishes are topped with crunchy, cheesy crust, this vegetable-based dish is hearty, filling, flavorful, and simple. Layers of heavy cream and shredded Gruyere cheese bind the sliced vegetables together in creamy, decadent casserole layers. The best part? You can make this easy vegetable casserole ahead of time and pop it in the oven on to save on day-of prep time. After about an hour, a fragrant casserole bubbling with melted cheese will emerge from the oven. But we can’t guarantee it’ll last that long on the table—your family or guests will gobble this one up. 


  • 1 large rutabaga, peeled and cut into 1/8-inch-thick slices
  • 2 large russet potatoes, peeled and cut into 1/8-inch-thick slices
  • 3 large parsnips, peeled and cut into 1/8-inch-thick slices
  • 1 1/2 teaspoons kosher salt
  • 1 1/2 cups heavy cream, divided
  • 8 ounces Gruyère cheese, shredded (about 2 cups), divided

How to Make

  1. Preheat oven to 400°F. Toss together rutabaga, potatoes, parsnips, salt, and 3/4 cup of the cream in a large bowl. Spread one-third of the mixture evenly in a lightly greased 11- x 7-inch baking dish; top with 3/4 cup of the Gruyère. Layer one-third of the rutabaga mixture, 3/4 cup of the Gruyère, and remaining rutabaga mixture and 3/4 cup cream. Top with remaining 1/2 cup Gruyère.
  2. Cover loosely with aluminum foil. Bake in preheated oven 45 minutes. Uncover and bake until vegetables are tender and cheese is golden brown, 20 to 25 minutes. Transfer to a wire rack; cool 5 minutes.