Root Vegetable Gratin

This vertically layered Root Vegetable Gratin, featuring vegetables in vibrant autumnal shades, is a noteworthy and unforgettable side dish.
Root Vegetable Gratin
I have a little crush on gratins. I love all the pretty layers, the savory scent of them baking in the oven, saying gratin in a fancy French accent. But I think what I love most about any sort of gratin is that it turns a side dish from an afterthought into something quite noteworthy.
That is especially the case with this Root Vegetable Gratin. Made with root vegetables in vibrant autumnal shades, it’s layered vertically rather than horizontally for maximum wow factor.
Root Vegetable Gratin


Just look at the gorgeous ombre layers in this Root Vegetable Gratin. It’s like sunset. On a platter! This is what we call winning at side dishes. Bring this to your Thanksgiving or Christmas feast and people will know right away that you’re not messing around.

What’s in this Root Vegetable Gratin:

  • Root vegetables like purple sweet potato, yams, and parsnips make up the majority of this dish. I also added butternut squash. Although not technically a root vegetable, its sweet flavors mingle nicely with the earthy root vegetables and balance the dish nicely.
  • A mixture of Gruyere, Parmesan, garlic, thyme and cream is used to bring the dish together while baking.
  • Extra cheese is sprinkled on top of the dish just before baking, and it’s garnished with additional fresh thyme after being removed from the oven.
Root Vegetable Gratin

Tips and Tricks:

  • Since baking dish sizes and shapes tend to vary, and so do sizes and shapes of root vegetables, plan on buying a bit extra of each vegetable to ensure that you will have enough to fill your baking dish.
  • The main thing to keep in mind when selecting your produce is to try to pick vegetables with a similar width/diameter. This will ensure that your slices are as uniform as possible and will make your gratin presentation appear neater.
  • A mandolin is the best tool to use for making sure your slices are an even thickness and will cook at the same rate.
  • Keep the dish covered with foil for the first 30 minutes or so of baking, then remove it for the remainder of baking time. That way when you add the cheese it gets nice and bubbly.


  • Try playing around with different root vegetables in this dish, such as rutabagas, beets, or regular potatoes. In another version I added golden beets and it was lovely!
  • Different cheeses such as raw cheddar, fontina or asiago would all work.
  • If you want to lighten up this dish, you can replace up to half of the heavy cream with vegetable broth.

autumn table under a tree

This Root Vegetable Gratin fit right in at a styled fall shoot I collaborated on last month with some local ladies at a nearby winery and farmstead called Folded Hills. The setting was sublime, the menu was completely swoon-worthy, and sipping on Folded Hills’ perfectly paired wines all afternoon was the cherry on top of an altogether splendid gathering.

Viktoriya from Fold styled the table to the nines, as usual, with her gorgeous eye for design and fabulous collection of linens and props.


Hana-Lee of Wander and Wine helped us pair our dishes with Folded Hills’ lineup of stunning wines. She also contributed a wonderful Roasted Squash Salad with Warm Cider Vinaigrette.


Robin of Cali Girl Cooking whipped up the main course, a Red Wine Roasted Chicken with Grapes and Herbs.


Becky from Baking the Goods rounded things out with a Spiced Up Grape Apple Pie.


Our friend Silas of Full Frame Photos captured the day beautifully in photographs.

Outdoor fall tablescape

Thanks for reading Le Petit Eats! To keep up with my kitchen escapades, follow me on FacebookInstagramTwitter and Pinterest.If you make this Root Vegetable Gratin, don’t forget to share it using the hashtag #LePetitEats!

Root Vegetable Gratin
5 from 1 vote

Root Vegetable Gratin

This vertically layered Root Vegetable Gratin, featuring vegetables in vibrant autumnal shades, is a noteworthy and unforgettable side dish
Course Side Dish
Cuisine Vegetarian
Keyword butternut squash, potato gratin, root vegetable gratin
Prep Time 30 minutes
Cook Time 1 hour 30 minutes
Total Time 2 hours
Servings 6
Calories 540 kcal
Author Denisse


  • 3 ounces finely grated Gruyère
  • 2 ounces finely grated Parmigiano-Reggiano
  • 2 cups heavy cream
  • 2 medium cloves garlic minced
  • 1 tablespoon fresh thyme leaves roughly chopped (plus more for garnish)
  • Salt and black pepper
  • 4 pounds assorted root vegetables such as yams purple sweet potatoes and parsnips, peeled and sliced 1/8-inch thick on a mandoline
  • 1/2 pound butternut squash neck only, peeled and sliced 1/8-inch thick on a mandoline
  • 2 tablespoons unsalted butter


  1. Heat oven to 400 degrees. Combine cheeses in a large bowl. Transfer 1/3 of cheese mixture to a separate small bowl and set aside. Add cream, garlic and thyme to the large bowl with cheeses. Season generously with salt and pepper.
  2. Grease a 2-quart casserole dish with butter. Working in batches, pick up a stack of each type of vegetable about 2-3 inches thick and slices and toss in the cream mixture until every slice is well coated. Neatly stack and lay in the casserole dish with the edges aligned vertically. Continue placing vegetables in the dish, working around the perimeter and into the center until the dish is packed tightly. Pour remaining cream mixture evenly over the vegetables just until the mixture comes halfway up the sides of the casserole, and discard any that remains.
  3. Cover dish tightly with foil and transfer to the oven. Bake for 30 minutes. Remove foil and continue baking until the top is pale golden brown, about 30 minutes longer. Remove from oven, sprinkle with remaining cheese, and return to oven. Bake until deep golden brown and crisp on top, about 30 minutes longer. Remove from oven, let rest for a few minutes, top with fresh thyme and serve.

Recipe Notes

Special Equipment: Mandoline


This vertically layered Root Vegetable Gratin, featuring vegetables in vibrant autumnal shades, is a noteworthy and unforgettable side dish perfect for any fall dinner or Thanksgiving table. #side #vegetables #gratin #thanksgiving #fallrecipes

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  1. Pingback: Spiced Up Grape Apple Pie - Baking the Goods

  2. Jen

    Would it be possible to make this the night before and then reheat it the next day? What advice do you have for making in advance?

    1. Denisse Post author

      Hi Jen, great question. I’d recommend assembling the entire dish the night before, then cover and refrigerate. Then bring it to room temperature first when you are ready to bake it the next day. Just let it sit out for about 30 mins-1 hour. I think it will taste more fresh that way vs. baking it the night before and reheating.

  3. betsy

    this is without a doubt the best gratin I’ve ever made or eaten! I’ve now made it 3 times in the last 3 weeks– holiday dinner parties – and each time it’s gotten raves. Two ingredients I used and will always use are fennel and golden beets – both a big flavor winners. I love thyme so I used 2x what’s in the recipe – I also used more garlic for the same reason.. each time I made it ahead and covered with foil to bake the next day and it took nothing away from the flavors. thanks so much for this recipe – what a winner!


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