Cheesy Root Vegetable Gratin
There are certain dishes that make the whole kitchen feel warm and inviting, and this Cheesy Root Vegetable Gratin is one of them. I first made it on a chilly weekend when I wanted a comforting side dish that felt a little more special than ordinary roasted vegetables. A family member suggested layering different root vegetables with cheese and herbs, and I decided to give it a try.
The result was even better than I expected. The vegetables became tender and creamy while the edges turned beautifully golden and bubbly. The combination of sweet potatoes, carrots, parsnips, and potatoes with garlic, thyme, and melted cheese made the whole dish smell incredible.
I made it for my family last weekend, and everyone loved it. Even the people who usually reach for the main dish first kept going back for another serving. Now, it’s something I make when I’m hosting family, celebrating a holiday, or simply craving a cozy homemade dinner.
If you love cheesy comfort food but want to sneak plenty of vegetables onto the table, this gratin is a wonderful recipe to keep nearby.
Why You’ll Love This Recipe
Creamy and cheesy
Packed with colorful root vegetables
Crispy golden top
Comforting homemade flavor
Perfect for family dinners
Beautiful enough for holidays and gatherings
Ingredients
2 medium Yukon Gold potatoes, thinly sliced
1 medium sweet potato, thinly sliced
2 medium carrots, thinly sliced
2 medium parsnips, thinly sliced
1 small rutabaga, thinly sliced, optional
1 small yellow onion, thinly sliced
3 garlic cloves, minced
1 cup heavy cream
½ cup whole milk
1 teaspoon fresh thyme leaves
½ teaspoon dried rosemary
½ teaspoon salt
¼ teaspoon black pepper
1 cup shredded Gruyère cheese
½ cup shredded Parmesan cheese
1 tablespoon extra virgin olive oil
2 tablespoons fresh parsley, chopped
Instructions
Step 1: Preheat the Oven
Preheat your oven to 375°F (190°C).
Lightly grease a 9×13-inch baking dish with olive oil.
Step 2: Prepare the Vegetables
Wash, peel, and thinly slice the root vegetables.
Try to keep the slices similar in thickness so they cook evenly.
Arrange the vegetables in alternating layers in the baking dish, adding the sliced onion between some of the layers.
Step 3: Make the Cream Sauce
In a small saucepan, combine the heavy cream, milk, minced garlic, thyme, rosemary, salt, and black pepper.
Warm over medium-low heat for about 3–4 minutes.
Don’t let the mixture boil.
Step 4: Add the Sauce
Slowly pour the warm cream mixture over the layered vegetables.
Gently press the vegetables down with the back of a spoon so the cream can reach between the layers.
Step 5: Add the Cheese
Sprinkle the Gruyère and Parmesan evenly over the top.
Cover the baking dish tightly with aluminum foil.
Step 6: Bake
Bake covered for 40 minutes.
Remove the foil and continue baking for another 20–25 minutes, until the vegetables are tender and the cheese is deeply golden and bubbling.
If you want an extra-crispy top, broil for 1–2 minutes at the end, watching carefully.
Step 7: Rest and Serve
Remove the gratin from the oven and let it rest for 10 minutes.
Sprinkle with fresh parsley and a little extra thyme.
Serve warm.
Tips for the Best Vegetable Gratin
Slice the vegetables thinly and evenly.
Don’t skip the resting time—it helps the creamy sauce thicken.
Covering the dish first helps the root vegetables become tender.
Remove the foil toward the end so the cheese can brown beautifully.
A mandoline can make slicing much easier, but use caution when handling it.
Gruyère gives a wonderfully nutty flavor, but cheddar or mozzarella can also work.
Mediterranean-Inspired Variation
For a Mediterranean twist, replace some of the heavy cream with extra virgin olive oil and add:
Fresh oregano
Crumbled feta
Roasted garlic
Thinly sliced zucchini
Roasted red peppers
Fresh parsley
You can also add a sprinkle of smoked paprika for extra depth.
Serving Suggestions
This gratin pairs beautifully with:
Herb-roasted chicken
Baked cod
Grilled salmon
Roast turkey
Grilled steak
Garlic herb shrimp
A simple cucumber and tomato salad
Roasted green vegetables
Storage
Store leftovers in an airtight container in the refrigerator for up to 4 days.
Reheat covered in a 350°F (175°C) oven until warmed through. You can uncover it for the final few minutes to crisp the cheese again.
Prep Time
20 minutes
Cook Time
65 minutes
Rest Time
10 minutes
Total Time
1 hour 35 minutes
Servings
8 servings
Nutrition (Approximate Per Serving)
Calories: 365
Protein: 11g
Carbohydrates: 32g
Fat: 22g
Fiber: 5g
Sugar: 7g
Sodium: 430mg
Nutrition is approximate and will vary depending on the vegetables, cheese, and cream used.
Frequently Asked Questions
What root vegetables work best in a gratin?
Potatoes, sweet potatoes, carrots, parsnips, rutabaga, turnips, and celery root all work well. Mixing several varieties gives the dish beautiful color and flavor.
Can I make this gratin ahead of time?
Yes. Assemble it earlier in the day, refrigerate it covered, and bring it close to room temperature before baking. You may need a little extra baking time.
Can I use different cheese?
Absolutely. Gruyère, cheddar, fontina, mozzarella, or a mixture of cheeses can all work. Parmesan is excellent for creating a golden, savory crust.
How do I keep the vegetables from staying crunchy?
Slice them thinly and evenly, cover the gratin for the first portion of baking, and make sure the cream sauce reaches throughout the layers.
Can I make this without heavy cream?
Yes. You can use whole milk or half-and-half for a lighter version, although the finished gratin will be less rich and creamy.
Is this a low-carb recipe?
Root vegetables are naturally higher in carbohydrates, particularly potatoes and sweet potatoes, so this isn’t a low-carb dish. For a lower-carb variation, replace some of the potatoes with zucchini, cauliflower, mushrooms, or turnips.