Name: Cheesy Root Vegetable Gratin Recipe
Prep time: 20 min
Cook time: 1 h
Total time: 1 h 20 min
Cuisine: American
Ingredients: 1-2 long sweet potatoes (about 2 inches thick), peeled; 3-4 large parsnips, ends trimmed and peeled; 3-5 small beets, peeled; 1 tablespoon unsalted butter, softened; 14 tablespoons heavy cream, divided (whole milk can be substituted, but mixture will be less creamy); 4 ounces grated Parmesan cheese, divided; 1 ounce shredded Gruyere cheese; 1 tablespoon fresh minced thyme, divided plus extra for garnish; 1 garlic clove, minced; Salt and pepper, to taste

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I’m so excited to share this Cheesy Root Vegetable Gratin Recipe with you—it’s one of those dishes that feels totally comforting but also elegant enough for company. The mix of sweet potatoes, parsnips, and beets creates this beautiful medley of flavors and textures, and layered with gooey cheese and thyme, it just melts in your mouth. Every time I make it, it fills the kitchen with this warm, inviting aroma that makes everyone gather around before dinner even starts.

This gratin works like magic during cozy fall and winter meals but honestly, I find myself making it year-round because the root vegetables give it such a satisfying heartiness. Plus, it’s a wonderful way to sneak in extra veggies without anyone realizing, thanks to the rich cheesy sauce. Trust me, once you try this Cheesy Root Vegetable Gratin Recipe, it’ll probably make an appearance on your table more often than you expect!

Ingredients You’ll Need

This recipe is all about fresh, wholesome ingredients that come together beautifully. When shopping, aim for firm and smooth-skinned root vegetables, and pick a good-quality cheese that melts well. It really makes a difference in flavor and texture.

Unsalted butter: Helps create a rich base without adding extra salt, so you control seasoning better.
Long sweet potatoes: Their natural sweetness is the backbone of the dish; pick firm ones without bruises.
Parsnips: Adds a lovely earthy and slightly sweet flavor that balances sweeter veggies.
Beets: Give a beautiful color pop and a subtle sweetness; peeling them carefully helps avoid stains.
Heavy cream: For that luscious, creamy sauce—whole milk works, but the cream thickens better.
Grated Parmesan: Offers sharp, salty depth and browns beautifully on top.
Fresh minced thyme: Brightens the dish with herbal notes, fresh is best but dried works in a pinch.
Garlic clove: Adds savory warmth; mince finely so it disperses evenly.
Shredded Gruyere: Melts wonderfully for that gooey, nutty cheese layer.
Salt and pepper: Essential for seasoning; I recommend tasting as you go.

Variations

One of the best things about this Cheesy Root Vegetable Gratin Recipe is how easy it is to tweak based on what’s in season or what you’re craving. I love encouraging you to make it your own because that’s where the magic happens.

Vegetarian version: Simply skip any meat additions (if you add them) and up the cheese and thyme for a fuller flavor. I do this often and it’s a huge hit.
Different cheese combos: Try swapping Gruyere with sharp cheddar or fontina for a twist—parmesan is a must for that salty punch though.
Seasonal veggies: Swap parsnips for turnips or add thinly sliced rutabaga; the texture is slightly different but still delicious.
Make it vegan: Use coconut cream or cashew cream, and a dairy-free cheese alternative—haven’t done it myself, but I hear it works well.

How to Make Cheesy Root Vegetable Gratin Recipe

Step 1: Prep Your Veggies

Start by peeling and slicing your sweet potatoes, parsnips, and beets into evenly thin rounds, about 1/8-inch thick. Use a sharp knife or mandoline if you have one to keep slices uniform, which helps them cook evenly. This step can be a bit time-consuming, but trust me, the consistency makes the final gratin so much better.

Step 2: Make the Creamy Cheese Mixture

In a small bowl, mix 3/4 of the Parmesan with shredded Gruyere, minced garlic, most of the fresh thyme, and about 12 tablespoons of the heavy cream. Season with salt and freshly ground pepper. This mixture is what turns the veggies into that creamy, cheesy delight you’re craving—make sure to taste and adjust the seasoning before layering.

Step 3: Layering the Gratin

Butter your baking dish with the softened unsalted butter to prevent sticking and add richness. Begin layering the root vegetables, alternating sweet potatoes, parsnips, and beets to create a colorful pattern. After a few layers, drizzle some of the cream and cheese mixture over the veggies, then continue layering. Finish with the remaining cream and cheese on top along with the last bit of Parmesan and thyme for a golden crust.

Step 4: Bake to Perfection

Cover the dish loosely with foil and bake in a preheated 375°F (190°C) oven for about 45 minutes. Then remove the foil and bake for another 15 minutes until the top is bubbling and beautifully golden. Keep an eye out for the bubbling cheese and tender veggies—it’s ready when you can easily pierce the veggies with a fork.

How to Serve Cheesy Root Vegetable Gratin Recipe

Cheesy Root Vegetable Gratin Recipe - Recipe Image

Garnishes

I’m a sucker for a simple garnish of fresh thyme sprigs right before serving—it gives the dish a pop of color and fresh aroma. Sometimes, I’ll sprinkle a touch of flaky sea salt on top right out of the oven for a little crunch and extra saltiness that sings against the creamy sauce.

Side Dishes

This gratin pairs wonderfully with roasted meats like chicken or pork, but it’s also fantastic alongside a crisp green salad to balance the richness. On lazy weekends, I serve it with a crusty bread and call it a hearty, comforting meal all on its own.

Creative Ways to Present

For a special gathering, I’ve layered this gratin in individual ramekins for a cute, personalized touch. It also looks stunning served in a clear glass dish so your guests can see all those colorful veggie layers—it’s like edible art that everyone asks about!

Make Ahead and Storage

Storing Leftovers

I usually let the gratin cool completely before covering it tightly with foil or plastic wrap, then pop it in the fridge. It keeps well for up to 3 days, and I find the flavors actually deepen overnight, making leftovers extra tasty.

Freezing

If I want to make it ahead for busy days, I freeze the unbaked gratin in a well-sealed dish. When I’m ready to eat it, I thaw overnight in the fridge and bake as usual. It sometimes takes a little longer to cook, but the texture stays creamy and delicious.

Reheating

Reheating in the oven at 350°F (175°C) with foil covering keeps the veggies moist and cheese melty—microwaving tends to dry it out, so I avoid that method. About 20 minutes usually does the trick for evenly warmed leftovers.

FAQs

Can I use other root vegetables in this Cheesy Root Vegetable Gratin Recipe?

Absolutely! Root veggies like turnips, rutabaga, or even celeriac can work wonderfully. Just slice them thinly to ensure even cooking and consider their sweetness and firmness to keep the balance of flavors harmonious.
What can I substitute for Gruyere if I can’t find it?

If Gruyere isn’t available, good melting cheeses like fontina, mozzarella, or sharp white cheddar can be great alternatives. The key is a cheese that melts smoothly and adds a mild nutty flavor similar to Gruyere.
Is it okay to use milk instead of heavy cream?

You can use whole milk, but the gratin won’t be quite as rich or thick because milk has less fat. To compensate, consider stirring in a little bit of flour or cornstarch to thicken the sauce slightly.
How do I prevent the root vegetables from getting mushy?

Slicing the vegetables thinly and evenly is crucial. Also, baking covered at first keeps moisture in without drying them out. If you notice the top browning too quickly, loosely cover with foil to avoid burning while the veggies cook through.
Can this Cheesy Root Vegetable Gratin Recipe be made ahead for gatherings?

Yes! You can assemble it the day before and refrigerate, then bake it on the day of your event. This actually enhances the flavors as they meld together. Just bring it to room temperature before baking for more even cooking.

Final Thoughts

This Cheesy Root Vegetable Gratin Recipe holds a special place in my heart because it’s both simple and impressive—perfect for everyday comfort or a fancy dinner. Whenever I make it, I’m reminded how food can be both nourishing and joyful. I hope you give it a try, tweak it to your liking, and make it part of your kitchen favorites too. It’s that kind of recipe that brings people together, and honestly, that’s what cooking is all about, isn’t it?