I have to tell you, this Cheesy Root Vegetable Gratin holds a special place in my heart after making it for the first time. The aroma alone is enough to make you impatient for dinner. Layers of tender root vegetables smothered in a creamy, cheesy sauce create the ultimate comfort food.
It’s the perfect side dish whether you’re hosting a family gathering or just want to treat yourself to something indulgent. The balance between the earthy sweetness of root vegetables and the savory cheese sauce will leave you (and everyone at the table) reaching for seconds. Trust me, once you make this recipe, you’ll want to keep it in your rotation!

Why You’ll Love This Recipe?
This dish isn’t just delicious; it’s so versatile and easy to prepare that you’ll find yourself making it often. Here’s why this recipe deserves a spot in your kitchen:
1. It’s Simple to Make
You don’t need to be a pro in the kitchen to nail this dish. From slicing veggies to creating the sauce, the steps are straightforward and beginner-friendly. Plus, most of the time is hands-off while the dish bakes in the oven!
2. Versatility at Its Best
This recipe can adapt to your preferences or dietary restrictions. Mix and match vegetables, use different cheeses, or even make it dairy-free if needed. It’s flexible enough to suit all tastes.
3. Perfect for Any Occasion
Whether it’s a weeknight dinner, holiday feast, or potluck, this gratin shines as a crowd-pleasing side dish. Its rich, cheesy layers feel special enough for guests but are comforting enough for a quiet family meal.
4. Packed with Flavor
The combination of creamy cheese, earthy root vegetables, and a hint of seasoning produces a dish that’s bursting with flavor in every bite. You’ll love the crispy golden top paired with the melt-in-your-mouth interior.
5. Easy to Customize
Don’t feel like sticking to the script? Toss in some fresh herbs, sprinkle on breadcrumbs, or even try a spicy cheese for a fun flavor twist. The possibilities are endless!
Cooking Time
Here’s how much time you’ll need to bring this masterpiece to life:
- Prep Time: 20 minutes
- Cooking Time: 60 minutes
- Total Time: 1 hour and 20 minutes
Ingredients
You’ll need the following to make this cheesy goodness:
- Potatoes
- Sweet potatoes
- Parsnips
- Carrots
- Onion
- Garlic
- Butter
- All-purpose flour
- Milk
- Sharp cheddar cheese
- Parmesan cheese
- Salt
- Black pepper
- Ground nutmeg (optional)
- Fresh thyme leaves (optional)
Variations
The versatility of this recipe is where the magic happens! Here are a few ways to make it your own:
- Dairy-Free: Use plant-based milk (like oat or almond) and vegan cheese.
- Low-Carb: Swap out starchy potatoes for lower-carb options like rutabaga or turnips.
- Extra Flavor Kick: Add a teaspoon of smoked paprika or chili flakes to the cheese sauce for a bold taste.
- Toppings: Sprinkle breadcrumbs or crushed crackers on top for an extra crunchy layer.
Equipment You’ll Need
To make your gratin, gather these tools:
- Mandoline slicer: For evenly slicing the vegetables.
- Saucepan: To prepare the cheese sauce.
- Baking dish: A 9×13-inch dish works perfectly.
- Whisk: To mix the roux and ensure a smooth sauce.
- Aluminum foil: Helps keep the veggies tender while baking.
How to Make Cheesy Root Vegetable Gratin?
Making this dish is easier than it seems. Here’s a step-by-step guide to create a gratin that will wow your tastebuds! 🧀
Step 1: Preheat the Oven
Start by preheating your oven to 375°F (190°C). Grease a baking dish with butter or cooking spray to prevent sticking.
Step 2: Prep the Veggies 🥕
Peel and thinly slice the root vegetables. A mandoline slicer works best here, giving you uniform slices that cook evenly. Place all the veggies in a large mixing bowl.
Step 3: Sauté Onion and Garlic 🧄
Melt butter in a saucepan over medium heat. Add sliced onion and garlic, cooking until they’re soft and aromatic. This step enhances the overall flavor base of the dish.
Step 4: Create the Cheese Sauce 🧀
Sprinkle flour over the onions and garlic, stirring constantly to make a roux. Gradually add milk, whisking as you go to prevent lumps. After the sauce thickens, lower the heat and stir in cheddar and Parmesan cheeses until the mixture is velvety smooth. Season with salt, pepper, and a touch of nutmeg if desired.
Step 5: Assemble the Gratin 🍂
Pour the rich cheese sauce over the sliced veggies in your bowl. Gently toss to ensure every piece is coated. Then, layer the veggies in your greased baking dish for an even distribution.
Step 6: Bake and Finish Cooking ⏲️
Cover the dish with foil and bake for 35-40 minutes. Remove the foil, sprinkle the remaining cheese on top, and return it to the oven for another 15-20 minutes until golden brown and bubbling.
Step 7: Serve and Enjoy
Allow the gratin to cool slightly before serving. Garnish with fresh thyme leaves for a burst of color and extra flavor. Voilà, your cheesy root veggie masterpiece is ready to savor!

Tips for Making the Recipe
- Even Slices Are Key: Thinner, uniform slices of vegetables ensure they cook evenly.
- Room Temperature Ingredients: Use room-temperature milk for a smoother cheese sauce.
- Don’t Skimp on Cheese: Good quality cheese makes a world of difference in flavor.
- Adjust Seasoning: Taste the sauce before layering to make sure the seasoning is spot-on.
How to Serve Cheesy Root Vegetable Gratin?
This dish deserves its moment to shine. Serve it alongside roasted meats, grilled fish, or even a fresh salad for a balanced meal. If you’re cooking for a special occasion, garnish it with fresh thyme or parsley, and serve it in the baking dish for a homey, rustic presentation.
Nutritional Information
Here’s what you can expect per serving:
- Calories: 320
- Protein: 8g
- Carbohydrates: 35g
- Fat: 15g
Make Ahead and Storage
You can prep this dish a day ahead! Assemble the gratin but hold off on baking. Cover it tightly with plastic wrap and store it in the fridge. When ready to serve, bake as directed, adding an extra 5-10 minutes to account for the cold start.
For leftovers, refrigerate the gratin in an airtight container for up to 3-4 days. Reheat portions in the oven to maintain the crispy top. Want to save it for later? Freeze individual portions for up to 3 months. Just make sure to thaw overnight in the fridge before reheating.
This video shows you how to make it:

Cheesy Root Vegetable Gratin Recipe
Ingredients
- Potatoes
- Sweet potatoes
- Parsnips
- Carrots
- Onion
- Garlic
- Butter
- All-purpose flour
- Milk
- Sharp cheddar cheese
- Parmesan cheese
- Salt
- Black pepper
- Ground nutmeg optional
- Fresh thyme leaves optional
Instructions
- Start by preheating your oven to 375°F (190°C). Grease a baking dish with butter or cooking spray to prevent sticking.
- Peel and thinly slice the root vegetables. A mandoline slicer works best here, giving you uniform slices that cook evenly. Place all the veggies in a large mixing bowl.
- Melt butter in a saucepan over medium heat. Add sliced onion and garlic, cooking until they’re soft and aromatic. This step enhances the overall flavor base of the dish.
- Sprinkle flour over the onions and garlic, stirring constantly to make a roux. Gradually add milk, whisking as you go to prevent lumps. After the sauce thickens, lower the heat and stir in cheddar and Parmesan cheeses until the mixture is velvety smooth. Season with salt, pepper, and a touch of nutmeg if desired.
- Pour the rich cheese sauce over the sliced veggies in your bowl. Gently toss to ensure every piece is coated. Then, layer the veggies in your greased baking dish for an even distribution.
- Cover the dish with foil and bake for 35-40 minutes. Remove the foil, sprinkle the remaining cheese on top, and return it to the oven for another 15-20 minutes until golden brown and bubbling.
- Allow the gratin to cool slightly before serving. Garnish with fresh thyme leaves for a burst of color and extra flavor. Voilà, your cheesy root veggie masterpiece is ready to savor!
Notes
- Even Slices Are Key: Thinner, uniform slices of vegetables ensure they cook evenly.
- Room Temperature Ingredients: Use room-temperature milk for a smoother cheese sauce.
- Don’t Skimp on Cheese: Good quality cheese makes a world of difference in flavor.
- Adjust Seasoning: Taste the sauce before layering to make sure the seasoning is spot-on.