Vegetable Au Gratin Recipe (Creamy Baked Vegetables)
Oct 09, 2024, Updated Mar 14, 2025
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Vegetable Au Gratin Recipe—The golden, bubbly cheese topping and colorful, tender vegetables make this dish beautiful and irresistible. It is impressive enough for a dinner party or Sunday supper yet simple enough for a family weeknight meal.
A gorgeous holiday side dish idea! Serve with pork chops or as a side after you learn how long to roast a whole chicken.
Why you’ll love this recipe
There’s something incredibly comforting about baked vegetables in a creamy, cheesy sauce with a golden topping. It’s the perfect blend of rustic and refined!
Vegetable au gratin is a fantastic way to use up abundant harvested vegetables. The mix of colors and textures makes each bite delightful, and the variety of vegetables ensures you get a good mix of vitamins and minerals. You will also love- Dad’s Potatoes Au Gratin, Baked Brie, and Creamy Sauce Cauliflower.
Check this out for more cozy fall dinner ideas!
Table of Contents
Simple Ingredients
This simple dish is made with a handful of fresh ingredients and pantry staples. We use fresh vegetables for the best results.
- Yellow Squash: Adds a mild, slightly sweet flavor and vibrant yellow color.
- Zucchini: Offers a similar mild flavor to squash but with a green hue.
- Sweet Potatoes or Yukon Gold Potatoes: Sweet potatoes bring a natural sweetness and rich orange color, while Yukon Gold potatoes offer a creamy texture and buttery flavor.
- Eggplant: Provides a slightly bitter taste and a soft, creamy texture when cooked.
- Olive Oil: Used to coat the vegetables, adding a rich flavor and helping them roast evenly.
- Dried Basil: Imparts a sweet, aromatic flavor that complements the vegetables.
- Salt: Enhances the natural flavors of the vegetables.
- Black Pepper: Adds a hint of spice and depth of flavor.
- Red Onion: Contributes a sharp, slightly sweet flavor and beautiful color.
- Butter: Forms the base of the béchamel sauce, adding richness.
- All-Purpose Flour: Thickens the béchamel sauce, creating a smooth, creamy texture.
- Whole Milk (or 2%): adds creaminess to the béchamel sauce. You can even use heavy cream.
- Fontina Cheese: Melts beautifully into the sauce, adding a mild, nutty flavor.
- Gruyère Cheese(or Mild White Cheddar): a rich, slightly nutty flavor and smooth melting texture.
- Parmigiano Cheese (parmesan cheese): add a salty, nutty flavor and a slightly grainy texture to the creamy sauce.
- Fresh Thyme, Rosemary, or Parsley: fresh, aromatic garnish to brighten the dish.
See the recipe card for quantities.
How to Make Vegetables Gratin
Follow these step-by-step pictures to make this stunning and versatile side dish or vegetarian main course. There are different ways to arrange the vegetables, but here is my version! More instructions are in the recipe card at the bottom of this post.
Make the Roasted Vegetables
Cut the vegetables into even slice rounds.
Season the vegetables.
Stack the seasoned veggies in an oval or square baking dish.
Bake the veggies for half of the total time.
Make the Bechamel Sauce and Assemble
Make the cheese bechamel sauce.
Start with a roux then add the milk.
Stir to thicken.
Add the cheeses and stir to combine.
Cook until the sauce is thick.
Vegetables after the first bake.
Pour the cheese sauce over the veggies and bake again.
Top the au gratin veggies with more cheese and bake for the final time until golden brown and bubbly.
The colorful layers of vegetables topped with golden, melted cheese make for a stunning presentation.
My Pro Tip
Recipe Tips
- Even Slicing: Use a mandolin or sharp knife to slice vegetables evenly for consistent cooking.
- Tight Packing: Arrange vegetable slices vertically and pack them tightly to ensure even cooking.
- Pre-Cook Vegetables: Partially cook dense vegetables like potatoes and sweet potatoes for tenderness.
- Cheese Selection: For a rich, complex flavor, use a mix of cheeses, such as fontina, Gruyere, and Parmigiano.
- Homemade Béchamel: Make béchamel sauce from scratch for a creamier, more flavorful dish.
- Optional Crispy Topping: Sprinkle additional cheese or a mix of panko breadcrumbs and cheese on top for a golden, crispy crust.
Substitutions and Variations
Vegetables- try different vegetables if you like!
- Yellow Squash and Zucchini: For a different flavor and color, you can substitute any summer squash or even thinly sliced carrots or cauliflower florets. Sweet Potatoes: Yukon Gold potatoes are a great alternative for a more classic gratin flavor. Regular russet potatoes can also be used for a starchier texture. Eggplant: Substitute with bell peppers or mushrooms for a different texture and taste.
Cheeses
- Fontina Cheese: Substitute with mozzarella or provolone for a similar melt and mild flavor. Gruyere Cheese: Use Swiss cheese or a mild white cheddar cheese. Parmigiano Cheese: Pecorino Romano or Asiago can be used for a similar sharp, nutty flavor.
Herbs and Seasonings
- Dried Basil: Substitute with dried oregano, thyme, or a mix of Italian seasoning. Fresh Thyme, Rosemary, or Parsley: Any fresh herbs like chives, dill, or even a sprinkle of fresh basil can be used for garnish.
Italian-Inspired Variation:
- Vegetables: Include layers of thinly sliced fennel and tomatoes.
- Cheese: Add mozzarella and a bit of ricotta for creaminess.
- Herbs: Use Italian seasoning blend with basil, oregano, and rosemary.
- Add-ins: Sprinkle some pine nuts or add slices of prosciutto for an authentic touch.
Storing and Reheating
- Storing:
- Cool completely. Refrigerate in an airtight container for 3-4 days. Freeze in freezer-safe containers for 2-3 months.
- Reheating: From the Refrigerator, Preheat the oven to 350°F (175°C). Cover with aluminum foil and bake for 20-30 minutes, uncovering for the last 5-10 minutes. From the Freezer, thaw overnight in the refrigerator, then bake as above. Microwave: Heat individual portions on medium power for 2-3 minutes, checking and continuing in 30-second increments until hot.
FAQs
“Au gratin” in French means “with a browned crust,” typically referring to dishes topped with cheese or breadcrumbs that are baked or broiled until golden and crispy.
More Recipes
Looking for other recipes? Try these:
Serving Suggestions
These are my favorite dishes to serve with this vegetable-baked dish:
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Vegetable Au Gratin Recipe (Creamy Baked Vegetables)
Ingredients
Vegetables
- 2 large yellow squash, sliced
- 2 large zucchini, sliced
- 2 sweet potatoes, or Yukon Gold potatoes, sliced
- 2 medium eggplants, sliced
- 1 tablespoon olive oil
- ½ tablespoon dried basil
- ½ tablespoon salt
- ½ tablespoon black pepper
- 1 small red onion, sliced
- Salt and ground black pepper to taste
Cheese Sauce
- 3 tablespoons butter
- 3 tablespoons all-purpose flour
- ½ teaspoon salt
- 2 cups whole milk, can use 2%
- 1 cup shredded fontina cheese, more for topping
- ½ cup shredded Gruyere cheese, or mild white cheddar, more for topping
- ½ cup shredded Parmigiano cheese, more for topping
- Fresh thyme, rosemary, or fresh parsley for garnish
Instructions
- Preheat your oven to 375°F (190°C).
- Thinly slice the zucchini, squash, eggplant, potatoes, and onion to about 1/4 – 1/2 inch thick using a sharp knife or mandolin.
- In a large bowl, toss all the sliced vegetables with olive oil, dried basil, 1/2 tablespoon of salt, and 1/2 tablespoon of black pepper. Ensure all vegetables are evenly coated.
- Arrange the Vegetables: Place the vegetables vertically in a large skillet or casserole dish, packing the slices tightly together, side by side.
- Bake the vegetables in the preheated oven for 25 minutes.
- Prepare the Béchamel Sauce: While the vegetables are baking, melt the butter in a saucepan over medium heat. Add the flour and cook, stirring constantly, for about 1-2 minutes to form a roux. Gradually add the milk, whisking continuously until the mixture is smooth and thickened. Stir in 1/2 teaspoon of salt.
- Add the shredded fontina, Gruyere (or white cheddar), and Parmigiano cheeses. Stir until the cheeses are completely melted and the sauce is smooth.
- Combine and Finish Baking: After 25 minutes, remove the vegetables from the oven. Pour the béchamel sauce evenly over the vegetables. Sprinkle additional shredded cheese on top for a golden, cheesy crust. Return the dish to the oven and bake for an additional 20-25 minutes, or until the top is golden brown and bubbly.
- Garnish and Serve: Remove the dish from the oven and let it rest for a few minutes. Garnish with fresh thyme, rosemary, or parsley. Serve warm and enjoy!
Notes
- Even Slicing: Use a mandolin or sharp knife to slice vegetables evenly for consistent cooking.
- Tight Packing: Arrange vegetable slices vertically and pack them tightly to ensure even cooking.
- Pre-Cook Vegetables: Partially cook dense vegetables like potatoes and sweet potatoes for tenderness.
- Cheese Selection: For a rich, complex flavor, use a mix of cheeses, such as fontina, Gruyere, and Parmigiano.
- Homemade Béchamel: Make béchamel sauce from scratch for a creamier, more flavorful dish.
- Optional Crispy Topping: Sprinkle additional cheese or a mix of panko breadcrumbs and cheese on top for a golden, crispy crust.
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
How would you prep this to cook the day of? Can it sit overnight before baking it?
Yes! Assemble the entire casserole and cover and refrigerate overnight. Let it come to room temp about 1 hour and then bake it! Enjoy.
Can’t wait to try this recipe!
You will LOVE it! Enjoy.
It’s like my dad’s famous au gratin potatoes recipe, but loaded with vegetables! You’ll love ti!
my husband said to give 5 stars, even though there is eggplant in it. it just goes to show that cheese makes everything better. I did have to make a trip to the store for the cheese, but it was worth it. presentation could not have been better!
WOW! So happy to happy hear this! I hope you enjoy time and time again.