Mixed Vegetable Casserole is a hearty side dish perfect for big family gatherings. Made easily with frozen veggies and a few pantry staples, you’ll love how simple this side dish really is. Great for parties, potlucks, or even as a meatless dinner option, this casserole is thrown together in no time and is a real crowd pleaser!
Check out our Vegetable Fried Rice and Air Fryer Cauliflower Florets for more amazing veggie sides. And try this Delicious Instant Pot Vegetable Soup Recipe for a warm dinner on a cold night.
Creamy Mixed Vegetable Casserole
Exhausted all of your dinner options but don’t want to trek to the store? Suddenly get invited to the neighborhood holiday potluck with no time to prepare?
No worries! This creamy mixed vegetable casserole has you covered.
Quickly toss together your favorite frozen veggies, some sautéed onions, melty cheddar cheese, cream of chicken soup, a dollop of mayo, and some savory seasonings.
Top it all off with buttered crackers for a satisfying crunch, and bake!
How to Make the Best Mixed Vegetable Casserole
A super easy casserole for those busy weeknights!
- Preheat your oven to 375°F and grease a baking dish.
- Bring a large pot of salted water to a boil and add the frozen vegetables. Cook for 1 to 2 minutes until softened. Drain and place the vegetables in a large, clean bowl.
- Heat a skillet over medium heat. Add the onions and butter and saute for 3 to 5 minutes. The onions should be translucent and slightly soft. Remove the skillet from heat.
- Combine the sautéed onions, cream of chicken (or celery) soup, water chestnuts, mayonnaise, garlic powder, and salt in a bowl. Stir in the mixed vegetables and add the shredded cheddar cheese.
- Transfer this mixture to the baking dish. Top with the crushed crackers and drizzle with melted butter.
- Bake the casserole for 10 to 15 minutes or until the filling is nice and bubbling and the crackers are browned.
- Serve warm and enjoy!
Tips for a Delicious Mixed Vegetable Casserole
- For a quick protein addition, shred some rotisserie chicken or pre cooked sliced sausage and toss it into the mix.
- Feel free to add any veggies you’d like or take out any you’re not a fan of. Mushrooms, beans, potatoes, peppers, cauliflower, whatever you have on hand!
- Sprinkle in some cajun seasoning or chili powder for a kick of flavor.
- While you can include whatever veggies you want, items like tomatoes or eggplant hold a lot of water and can make the casserole a bit too soupy.
Storage: Store leftover mixed vegetable casserole in an airtight container in the refrigerator for up to 5 days.
You can make this casserole the day before and keep covered in the fridge. Bake as directed when ready to serve.
Reheating: Reheat this casserole in the oven at 375°F until warmed through, or heat individual servings in the microwave for a couple minutes.
Is this recipe vegetarian?
If you use cream of chicken soup it won’t be considered a completely vegetarian dish. However if you swap the cream of chicken for cream of celery it is a fully vegetarian recipe! Be sure to check the labels on the ingredients to be 100% sure.
Do I have to use frozen veggies?
You do not. Fresh, frozen, or canned veggies will all work for this recipe. It’s perfect for using up leftovers or when you’re down to canned goods because you’ve been putting off that trip to the grocery store.
Make sure canned veggies are drained of all their liquid to keep the casserole from being too watery. Fresh veggies need to be blanched for a couple minutes ahead of time since we aren’t cooking this casserole very long.
Are mixed vegetables healthy?
This is probably debatable depending on who you ask. The frozen mixed vegetables in this casserole are just that, frozen vegetables. No sauce, no salt, no seasonings, no frills. By themselves, they may be considered a healthy side dish.
Toss them into a cream of chicken soup and top with some buttery crackers, and you’ve got a different story altogether. This casserole “might” be healthier than other casseroles, but it’s still a casserole. So it’s not the healthiest dish out there.
Can you make mixed vegetable casserole with cream of mushroom soup?
Sure! We love to make this mixed vegetable casserole with cream of chicken soup, but feel free to use whatever variety of condensed soup you prefer.
Can you make mixed vegetable casserole without cheese?
Absolutely! Simply omit the cheese. Bake as written in the instructions and you’re good to go.
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- 20 ounces frozen mixed vegetables 2 (10 ounce) packages
- ½ cup white onion diced
- 1 tablespoon unsalted butter
- 10 ½ ounces cream of chicken soup may also use cream of celery soup
- 8 ounces water chestnuts drained
- ⅓ cup mayonnaise
- ½ teaspoon garlic powder
- ½ teaspoon salt or to taste
- 1 cup sharp cheddar cheese shredded off the block
- 2 cups butter crackers crushed (about 1 sleeve; similar to Ritz crackers)
- 3 tablespoons unsalted butter melted
- Preheat the oven to 375°F, and grease a 2 quart baking dish.
- Bring a large pot of salted water to a boil, and add the frozen vegetables. Cook for 1 to 2 minutes. Drain and place the vegetables in a large, clean bowl.20 ounces frozen mixed vegetables
- Heat a medium skillet over medium heat. Add the onions and butter, and saute for 3 to 5 minutes until the onions begin to soften. Remove from heat.½ cup white onion1 tablespoon unsalted butter
- Combine the sauteed onions, cream of chicken soup, water chestnuts, mayonnaise, garlic powder, and salt. Add the cream of chicken soup mixture to the vegetables and stir to combine then mix in the cheddar cheese.10 ½ ounces cream of chicken soup8 ounces water chestnuts⅓ cup mayonnaise½ teaspoon garlic powder½ teaspoon salt1 cup sharp cheddar cheese
- Transfer the mixture to the prepared baking dish. Top with crushed crackers, and drizzle with melted butter.2 cups butter crackers3 tablespoons unsalted butter
- Bake uncovered for 15 to 20 minutes or until the filling bubbles and the crackers are browned.
- Serve warm! See post for tips, FAQs, and storage options.