Cheesy Root Vegetable Gratin

Prep time: 15 minutes
Cook time: 50 minutes

  • 1 tablespoon unsalted butter softened
  • 1-2 long sweet potatoes (about 2 inches thick), peeled
  • 3-4 large parsnips, ends trimmed and peeled
  • 3-5 small beets, peeled
  • 14 tablespoons heavy cream, divided
    (whole milk is fine, but mixture won't thicken as much or be as creamy)
  • 4 ounces grated Parmesan, divided
  • 1 tablespoon fresh minced thyme, divided plus more for garnish
  • 1 garlic clove, minced
  • 1 ounce shredded gruyere
  • salt and pepper to taste
  1. Preheat oven to 400˚F. Grease a 3 quart baking dish with butter.
  2. Slice sweet potato, parsnips and beets into very thin rounds (using a mandoline is easiest) and transfer each vegetable to its own bowl.
  3. Pour 4 tablespoons cream over each sweet potatoes and parsnips, and 2 tablespoons cream over beets. Top each bowl of sliced vegetables with ½ ounce grated Parmesan and 1 teaspoon minced thyme. Season each bowl generously with salt and pepper and toss together until all vegetable slices are well coated.
  4. Pour remaining 1/4 cup cream into the bottom of a 3 quart (oval) baking dish and sprinkle with ½ ounce of Parmesan and minced garlic.
  5. Grab a stack of sweet potatoes and line them standing up on a bias, at the top of the baking dish. Follow the sweet potato with a row of parsnips, followed by a row of beets. Repeat with the remaining sweet potatoes, parsnips and beets, creating 6 rows of root vegetables.
  6. Season top of gratin with salt, pepper and sprinkle of remaining Parmesan.
  7. Cover with foil and bake for 30 minutes or until vegetables are soft.
  8. Uncover gratin and top with shredded gruyere.
  9. Place gratin back into oven, uncovered, and continue to bake for an additional 18 to 20 minutes or until vegetables are fork tender, cheese has melted and the top has lightly browned.
  10. Finish with a sprinkle of fresh thyme leaves. Serve.
*Makes 1 (3 quart) casserole
*Nutrition facts are based on the lowest number vegetables in each range in the ingredient list

  • This dish can be made up to a day ahead of time and refrigerated, tightly wrapped in foil. When ready to bake, just place the covered gratin in the oven, adding about an extra 5-7 minutes of baking time to the dish (covered).
    **Just know that if you prep this dish ahead of time, you run the risk of the beets bleeding from sitting in the cream. This won’t effect the flavor at all, but it’ll change the look of this dish.**
  • To prevent the beets from bleeding:
    • Make sure the peeled and sliced beets are just barely coated in cream to ensure they don’t dry out while baking.
    • You also want to make sure the bottom layer of your baking dish is just coated with a thin layer of cream and sprinkled with Parmesan. The amount of cream used may vary just a little bit, depending on the surface area of the baking dish you’re using, so it’s best to eyeball this.