Vegetable Au Gratin Recipe (Creamy Baked Vegetables)

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!