Vegetable Casserole (original) (raw)

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When you just can’t choose a single vegetable for your holiday casserole, make this Vegetable Casserole with the best of all worlds! This recipe starts with frozen veggies to make it quick and easy, and it has a creamy-dreamy cheese sauce and crispy panko topping. Yum!

Why You’ll Love This Cheesy Mixed Vegetable Casserole Recipe

• Cheesy, Creamy Veggie Casserole. It’s not just creamy! This vegetable casserole recipe has a rich cheese sauce reminiscent of other cheesy vegetable recipes like Cheesy Broccoli and Cauliflower “Mac” and Cheese. And no one can resist cheesy veggies—it’s just a fact.
• Super Versatile. While I made this vegetable casserole with peas, carrots, and broccoli, you can swap in any vegetables you like. Consider this recipe a template to create your own casserole masterpiece.
• Easy to Make. With frozen veggies as the base, this casserole comes together quickly and easily. Aside from the onion and garlic, there’s no fresh produce to prep!

How to Make Vegetable Casserole

The Ingredients

• Unsalted Butter. This is for cooking the aromatics, and then it’s incorporated into the roux for the sauce.
• Yellow Onion and Garlic. The aromatics that build the flavor of the sauce.
• Frozen Vegetables. I used a bag of frozen peas and carrots and a bag of broccoli. Thaw the frozen vegetables and drain off any excess water.
• All-Purpose Flour. To thicken the sauce.
• Broth. Vegetable broth or low-sodium chicken broth both work.
• Whole Milk. Use cream or half and half instead of milk for a richer version.
• Shredded Cheddar Cheese. Use a good, sassy cheddar, but avoid ones that are aged several years; their crumbly texture makes them less-than-ideal for melting into a smooth cheese sauce.
• Topping. Stir together butter, panko, and kosher salt for that fabulously crispy breadcrumb topping.

The Directions

1. Cook the Onion. Sauté the onion with the butter, salt, and pepper in a skillet over medium heat.

1. Add the Veggies and Garlic. Stir them into the onions and cook until the veggies soften a bit.

1. Cook the Flour. Sprinkle it over the vegetables, then stir it in and cook for a minute, or until the flour turns golden.

1. Add the Broth. Stir and scrape the bottom of the pan to incorporate any browned bits into the sauce. Increase heat to a simmer, cook for a minute, then turn off the heat.

1. Make It Cheesy. Stir in the milk and a cup of cheese, then transfer the veggie mixture to a casserole dish.

1. Prep the Topping. Combine the melted butter, panko, and salt.

1. Finish. Sprinkle the panko over the casserole, followed by the reserved cheese. Bake the vegetable casserole at 350 degrees F for 15 to 20 minutes, or until the top is golden brown. Cool for 5 minutes, then ENJOY!

Recipe Variations

• Try a Different Topping. Crumbled buttery crackers (like Ritz) or cornflakes (Midwest represent!) would make excellent toppings for this casserole. You’ll still want to stir them with melted butter, but you can skip the added salt if you use crackers.
• Switch Up the Cheese. I think gouda and gruyere would both work quite well in this vegetable casserole.

What to Serve with Vegetable Casserole

• Holiday Favorites. This casserole is a great side dish to serve with all your holiday favorites like Mushroom Gravy, Garlic Mashed Potatoes, and Baked Ham.
• Weeknight Mains. Easy main dishes like Baked Bone In Chicken Breast, Air Fryer Pork Chops, and Turkey Meatloaf are perfect with vegetable casserole.
• Bread. Soak up the sauce with Crock Pot Bread or Roasted Garlic Potato Rolls.

Recipe Tips and Tricks

• Shred Your Own Cheese. Pre-shredded cheese is coated in a powdery anti-caking agent that affects the way it melts. For the best results—a smooth, creamy cheese sauce—buy a block of cheddar and shred it yourself.
• Thaw the Frozen Vegetables Completely. Then be sure to drain off the excess water before adding them to the casserole to prevent the dish from becoming water-logged.
• Don’t Make It Ahead. Unfortunately, making this vegetable casserole ahead of time is likely to result in a soggy texture. (I don’t recommend freezing this casserole for the same reason.) If you’re looking for a good make-ahead casserole for the holidays, try my Broccoli Rice Casserole or Sweet Potato Casserole Recipe. Be sure to check out my free Thanksgiving menu planning guide too for more ideas!

This creamy and cheesy mixed vegetable casserole recipe is super easy and knock-your-socks-off delicious! Only needs 5 minutes of prep!

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• 4 tablespoons ½ stick unsalted butter
• 1 medium yellow onion thinly sliced (about 1½ cups)
• 1 teaspoon kosher salt
• ½ teaspoon ground black pepper
• 3 garlic cloves minced (about 1 tablespoon)
• 1 (12-ounce) bag frozen peas and carrots mix thawed and drained of excess water
• 1 (12-ounce) bag frozen broccoli thawed and drained of excess water
• 3 tablespoons all-purpose flour
• ½ cup vegetable broth or low-sodium chicken broth
• ½ cup whole milk
• 1 ¼ cups shredded cheddar cheese divided

• Place a rack in the center of the oven and preheat the oven to 350°F. Coat an 8×8-inch baking dish with nonstick spray.

• Melt the butter in a large skillet over medium heat. Add the onion, salt, and pepper and cook, stirring regularly, until softened, about 6 minutes. Add the garlic and frozen vegetables and cook for 2 to 3 minutes, until starting to soften.
  

• Sprinkle the flour over the vegetable mixture and cook, stirring, until toasty golden, and dry, about 1 minute.
  

• While stirring, slowly pour in the broth, breaking up any clumps of flour and scraping browned bits off the bottom of the pan.
  

• Increase the heat to a simmer. Let simmer 1 minute, then turn off the heat. Stir in the milk and 1 cup of cheese.

• Transfer the mixture to the prepared baking dish.
  

• Make the topping: In a small bowl, melt the butter. Stir in the panko and salt. Sprinkle the topping and the remaining ¼ cup cheese over the casserole.
  

• Bake for 15 to 20 minutes, until the top is golden-brown. Let cool for at least 5 minutes before serving.

• TO STORE: Refrigerate leftovers wrapped in the casserole dish or in an airtight container for up to 4 days.

• TO REHEAT: Warm small portions of leftovers in the microwave, or pop the casserole dish back in a 350ºF oven until the casserole is warmed through.

• TO FREEZE: I do not recommend freezing, but if you have leftovers that you won’t eat within 4 days, you can transfer them to an airtight container and store for up to 6 months. Thaw in the refrigerator and drain off any excess liquid before reheating.

Serving: 1(of 6)Calories: 267kcalCarbohydrates: 17gProtein: 10gFat: 19gSaturated Fat: 11gPolyunsaturated Fat: 1gMonounsaturated Fat: 4gTrans Fat: 0.4gCholesterol: 51mgPotassium: 216mgFiber: 3gSugar: 2gVitamin A: 5958IUVitamin C: 10mgCalcium: 228mgIron: 1mg

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Hi, I’m Erin Clarke, cookbook author and the home cook behind Well Plated. I’ve helped millions of people cook healthier meals that actually taste amazing and sold over 200,000 books! I’m here to help you save time, dirty fewer dishes, and feel great about what you’re eating, without overthinking it. Welcome!

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