When you want a side dish that’s both cozy and impressive, this Cheesy Root Vegetable Gratin | Spoon Fork Bacon delivers every time. I first made it during the holidays when I wanted something beyond the usual mashed potatoes. Layered with colorful root vegetables, creamy sauce, and plenty of melted cheese, this gratin is indulgent yet full of earthy flavor. The crispy golden top paired with tender veggies underneath makes it perfect for family gatherings, Sunday dinners, or even Thanksgiving. It’s rustic, flavorful, and guaranteed to win over the table.
Ingredients
2 tbsp butter
1 tbsp olive oil
1 large onion, thinly sliced
3 garlic cloves, minced
2 large russet potatoes, peeled and thinly sliced
2 carrots, peeled and sliced
2 parsnips, peeled and sliced
1 small sweet potato, peeled and sliced
1 turnip, peeled and sliced
2 cups heavy cream
1 tsp thyme
1 tsp rosemary
2 cups shredded Gruyère cheese
1 cup Parmesan cheese, grated
Salt and black pepper, to taste
Fresh parsley, for garnish
Instructions
Preheat oven to 375°F (190°C) and grease a baking dish with butter. In a skillet, melt butter and olive oil, then sauté onion and garlic until soft and fragrant. Layer half of the root vegetables in the dish, season with salt, pepper, thyme, and rosemary. Pour half the cream mixture over and sprinkle with half the cheeses. Repeat layers with remaining vegetables, cream, and cheese. Cover with foil and bake for 40 minutes. Remove foil and bake an additional 20 minutes until golden and bubbly. Garnish with parsley and serve hot.
Substitutions
Swap heavy cream for half-and-half if you prefer it lighter. Use cheddar or mozzarella instead of Gruyère for a more budget-friendly version. Sweet potatoes or beets can replace turnips or parsnips for extra sweetness. Vegan version: use plant-based cream and dairy-free cheese.
Equipment
Mandoline or sharp knife for slicing vegetables
Large skillet for sautéing
Mixing bowl for cream and herbs
9×13 baking dish
Aluminum foil
Oven mitts
Storage
Refrigerator: Store covered for up to 4 days.
Freezer: Freeze baked gratin in portions up to 2 months. Thaw overnight before reheating.
Reheating: Warm in oven at 350°F until hot; cover with foil to keep from drying out.
Top Tips
Slice vegetables thin and even for uniform cooking. Always cover with foil first to steam, then uncover for crisp topping. Use freshly grated cheese for better melting and flavor. Let gratin rest 10 minutes before serving so layers set.
FAQs
Can I make this gratin ahead of time? Yes, assemble up to a day ahead and refrigerate, then bake before serving.
What vegetables work best? A mix of potatoes, carrots, parsnips, and sweet potatoes works beautifully, but you can add rutabaga or beets too.
Can I make it without cream? Yes, whole milk thickened with a roux is a good alternative.
Is this dish gluten-free? Yes, as long as your cheeses and cream are gluten-free.