There’s something undeniably comforting about the aroma of roasting root vegetables filling your kitchen. This Root Vegetable Gratin with Sweet Potatoes, Parsnips, and Beets brings together earthiness, creaminess, and a golden, bubbly top — it’s everything I love in a seasonal side dish. Whether you’re gathering for a holiday meal or just craving something wholesome yet indulgent, this gratin offers the perfect blend of rustic charm and refined flavor.
This recipe holds a dear place in my autumn table rotation, but its vibrant colors and flexible nature make it suitable year-round. As we dive into the hows and whys, I encourage you to subscribe to Recipes by Sylvia for more heartfelt dishes that bring people together.
A Rooted Memory: How This Gratin Became a Family Favorite
The Inspiration Behind This Gratin
My love for this dish began in my grandmother’s farmhouse kitchen. She used to slice sweet potatoes paper-thin with her favorite mandoline, laying them like fallen leaves in a baking dish. We’d gather around her table on crisp November evenings, devouring layers of sweet, nutty, and earthy vegetables smothered in cream. That original inspiration led me to create a more colorful version, one that celebrates the humble beauty of root vegetables — particularly sweet potatoes, parsnips, and beets.
Each time I make this gratin, I’m brought back to that warmth — the creak of the old wood floors, the sound of laughter bouncing off floral wallpaper, and the smell of bubbling cream and thyme.
Why This Recipe Stands Out
Unlike traditional potato gratins, this dish leans on naturally sweet and vibrant root vegetables. The combination of beets, parsnips, and sweet potatoes adds depth and color that transforms a simple side into the star of the table. The creamy garlic sauce, a touch of sharp cheese, and the caramelization from slow baking elevate each layer.
It pairs beautifully with hearty mains and feels right at home alongside fresh dishes like Greek Smashed Potatoes with Feta or the light and flavorful Beet Salad with Feta, Cucumbers, and Dill.
From Roots to Richness: What You’ll Need to Make It
Ingredient Breakdown
Here’s what brings this gratin together. Feel free to adapt quantities depending on your baking dish size.
| Ingredient | Amount | Notes |
|---|---|---|
| Sweet potatoes | 2 medium | Peeled, thinly sliced |
| Parsnips | 2 medium | Peeled, thinly sliced |
| Beets | 2 medium | Peeled, thinly sliced |
| Garlic | 3 cloves | Minced |
| Heavy cream | 1 ½ cups | Can sub with half-and-half |
| Gruyère cheese | 1 cup shredded | Or sharp cheddar |
| Thyme | 1 tsp | Fresh or dried |
| Olive oil | 2 tbsp | For drizzling |
| Salt & pepper | To taste | Adjust to preference |
These ingredients provide a beautiful balance of color, texture, and taste — creamy and crisp, sweet and savory.
Tools & Substitutions
You’ll need a mandoline slicer or sharp knife, a 9×13-inch baking dish, and a saucepan for warming the cream. While Gruyère adds a nutty bite, don’t hesitate to substitute with parmesan or sharp cheddar for a more budget-friendly option.
If you’re seeking a dairy-free version, swap cream for coconut milk and use a vegan cheese substitute — just like we do when making the Vibrant Roasted Beets and Carrots with Creamy Burrata Salad, which is easily adaptable.
Layer by Layer: Making the Perfect Root Vegetable Gratin
Step-by-Step Instructions
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Prep the Vegetables
Peel and slice your sweet potatoes, parsnips, and beets into thin rounds (about ⅛ inch thick). Keep them separate to preserve their beautiful hues. -
Make the Cream Mixture
In a saucepan over medium heat, combine garlic, cream, thyme, salt, and pepper. Simmer for 3–5 minutes until infused and fragrant. -
Layer the Gratin
Grease your baking dish. Arrange a layer of sweet potatoes, followed by parsnips and beets. Repeat until the dish is nearly full. Pour cream mixture evenly over the vegetables and sprinkle with shredded cheese. -
Bake Until Bubbly and Golden
Cover with foil and bake at 375°F for 35 minutes. Uncover and bake an additional 20–25 minutes until the top is golden and bubbly.
Tips for Gratin Success
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Slice evenly: uniform thickness ensures consistent baking.
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Let it rest: cool for 10 minutes before serving so it holds together.
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Make ahead: assemble the night before and bake when ready.
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Cheese crust: broil the top for 2 minutes for extra crispiness.
These tips also apply beautifully when making creamy dishes like the Savory Mushroom Gruyère Puff Pastry Braid where texture is everything.
How to Serve, Store & Love Your Gratin
What to Serve With It
This dish is a natural partner to roasts or simple proteins. Try it alongside Rolled-Up Chicken with Feta, Spinach, and Sun-Dried Tomatoes or something lighter like Avocado Strawberry Caprese Salad.
For a more indulgent winter spread, add Stuffed Sweet Potatoes with Spinach, Avocado, and Feta to your menu.
Storing & Reheating Leftovers
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Fridge: Store in an airtight container for up to 4 days.
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Freezer: Wrap tightly and freeze up to 2 months. Thaw overnight in the fridge before reheating.
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Reheat: Cover with foil and warm in a 350°F oven for 15–20 minutes.
The flavors intensify beautifully by day two, making this a prime make-ahead candidate just like our cozy Southwest Sweet Potato Skillet.
FAQs About Root Vegetable Gratin
Can I make this dairy-free?
Yes! Use coconut cream and dairy-free cheese. The flavor will shift slightly but remain rich.
What’s the best way to slice the vegetables?
A mandoline works best, but a sharp chef’s knife will also do the trick with a little patience.
Do the beets bleed into the other vegetables?
Yes, slightly — layer them on top or bottom to preserve the visual contrast.
Can I add meat?
Sure! Layer in thin slices of cooked bacon or pancetta between the veggies.
What other root veggies can I use?
Try rutabaga, turnips, or celery root. Just make sure everything is sliced evenly.
A Dish to Remember
This Root Vegetable Gratin delivers more than just beautiful colors and creamy layers — it’s comfort in a pan. Whether it’s gracing your holiday spread or adding warmth to a weeknight meal, it’s a dish you’ll come back to again and again.
If you enjoyed this, you’ll also love Burrata, Beet & Sweet Potato Stacks or the creamy indulgence of Roasted Beets and Sweet Potatoes with Feta.
If you loved this recipe, don’t forget to leave a rating, comment below, and save it to your Pinterest board at Recipes by Sylvia on Pinterest!
Print
Root Vegetable Gratin with Sweet Potatoes, Parsnips, and Beets
- Total Time: 75
- Yield: 6 servings
- Diet: Vegetarian
Description
Root Vegetable Gratin with Sweet Potatoes, Parsnips, and Beets is a creamy, colorful, and comforting side dish featuring layers of thin-sliced root vegetables baked in a garlic-thyme cream sauce, topped with melted cheese.
Ingredients
• 2 medium sweet potatoes, peeled and thinly sliced
• 2 medium parsnips, peeled and thinly sliced
• 2 medium beets, peeled and thinly sliced
• 3 cloves garlic, minced
• 1 ½ cups heavy cream
• 1 cup shredded Gruyère cheese (or sharp cheddar)
• 1 tsp thyme (fresh or dried)
• 2 tbsp olive oil
• Salt and pepper to taste
Instructions
1. Preheat oven to 375°F and grease a 9×13-inch baking dish.
2. Peel and slice sweet potatoes, parsnips, and beets into 1/8-inch rounds.
3. In a saucepan, heat cream with garlic, thyme, salt, and pepper. Simmer 3–5 minutes.
4. Layer vegetables in the dish, alternating by color. Pour cream evenly over layers.
5. Top with shredded cheese and cover dish with foil.
6. Bake covered for 35 minutes. Uncover and bake 20–25 more minutes until bubbly and golden.
7. Let gratin rest 10 minutes before serving to set layers.
Notes
– Use a mandoline slicer for uniform slices.
– You can prep the gratin a day ahead and bake when ready.
– Substitute coconut milk and vegan cheese for a dairy-free version.
– Add crispy pancetta or bacon between layers for extra richness.
– Great for holidays or cozy winter dinners, pairs beautifully with roasted meats or a crisp salad.
- Prep Time: 20
- Cook Time: 55
- Method: Baked
- Cuisine: American