
Are you looking for some vegetarian casserole recipes or baked vegetable casserole for a side dish? This mixed vegetable casserole is a wonderful idea for any occasion, be it holidays, get-togethers, or a potluck.
The melting taste of steamed mixed veggies in creamy white sauce, baked to perfection with some cheese on the top, is sure to please a lot of taste buds!
Ingredients
You can pick from a wide variety of vegetable combinations like carrots, green beans, corn, cauliflower, broccoli, spinach, mushrooms, or any other favorite veggies of your choice for this veggie casserole recipe.
Avoid using vegetables (like eggplant, and tomatoes) that release too much water else the veggie casserole may turn out to be runny.
You will need milk, all-purpose flour, butter for the white sauce, and some shredded cheddar cheese and other cheeses for the topping. Garlic and spicy pepper can be used as per taste for enhancing flavor.
Substitutions
You can use frozen vegetables or a mix of fresh and frozen vegetables in a casserole. You can also chop and freeze fresh vegetables and then use them.
Instructions
The veg casserole can be made in three easy and quick steps. Instant Pot cooks the veggies to perfection in just a few minutes.
The white sauce can be made while the veggies are cooking. Finally, bake the mixed vegetables, sauce, and cheese in a baking dish in the oven.

In the Instant Pot container, add about half a cup of water. I am using 6 qt. Instant Pot. Add all the vegetables to a steamer basket. Pressure cook the vegetables for zero, yes "zero" minutes.
As soon as the Instant Pot comes to full pressure and turns off, do a quick release manually and release all the pressure, but carefully. Quick-release ensures that vegetables are cooked to perfection.

While the veggies are cooking in the Instant Pot, prepare the white sauce on the cooktop. In a pan, heat and melt butter. Optionally add some garlic and green chili paste, chopped ones work well too. Mix well.
Check out my recipe to make garlic paste at home.
Add little all-purpose flour and cook for about 30 seconds until it is well incorporated into the butter.
Add milk, and salt and once it gets bubbly, add some shredded cheese, I like to use cheddar or pepper jack, but you can use cheese of your choice. Once the sauce thickens, turn off the flame.

Preheat the oven to 400 °F. Mix the steamed vegetables and white sauce gently and pour into a casserole dish.
Sprinkle some shredded cheese on top of it, a hand grater comes in handy while grating cheese. I like sharp cheddar cheese, swiss cheese, or pepper-jack but you can use any cheese of your choice.
Bake the casserole dish in the oven for about 20 minutes until the cheese melts and becomes golden brown.

Serving suggestions
This baked veg casserole recipe is easy to make and can be served as a side dish. It goes well with French bread, sourdough bread, garlic knots, breadsticks, or any other bread.
Storage
Any leftover casserole can be stored in the fridge for 2-3 days in an airtight container. When you are ready to eat, simply reheat it in the microwave.

Don't forget to check out these recipes for parties and potlucks
- Vegetable pasta casserole
- Samosa chaat
- Baked broccoli pasta
- Sev puri chaat
- Cheesy garlic pull-apart rolls
- Mac and cheese
- Veg sizzler
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📖 Recipe

Mixed Vegetable Casserole
Equipment
- Convection Oven
Ingredients
Vegetables
- 1 cup Green beans (100 grams, chopped)
- 1 cup Carrots (100 grams, diced)
- 1 cup Corn kernels (Frozen or fresh)
- 1 cup Cauliflower florets (100 grams)
- 3 cup Spinach or Baby spinach (100 grams)
- ½ cup Water
White Sauce
- 1 cup Milk
- 1 ½ tablespoon All purpose flour
- 1 ½ tablespoon Unsalted butter
- 1 teaspoon Garlic paste
- 1 teaspoon Green chillies (paste or chopped)
- ¼ cup Cheddar cheese (or any other cheese)
- ½ teaspoon Salt (to taste)
Baking Casserole
- ½ cup Cheese (pepper jack, cheddar, Swiss or other)
Instructions
Steaming veggies in Instant Pot
- Put ½ cup water in the Instant Pot liner.
- Put all the veggies in the streamer basket and close the lid.
- Pressure cook for Zero minutes with pressure valve in sealing position.
- Do a quick release and open the lid.
Make white sauce
- On the cook top, heat a skillet on medium flame.
- Add butter, once butter melts add green pepper, garlic paste and mix well.
- Add all purpose flour and cook for about 30 seconds and mix well.
- Add milk followed by salt and mix well.
- Once milk starts bubbling and thickening, add some cheese.
- Stir well until the cheese melts and sauce thickens.
- Take it off the flame.
Baked casserole steps
- Preheat oven to 400 °F
- Add all the steamed vegetables in the white sauce and gently mix
- In a casserole dish, pour the sauce and veggies.
- Cover with grated cheese and bake for about 20 minutes until cheese melts and becomes brown
Notes
You may also like these 20+ Indian instant pot kid-friendly vegetarian recipes.
Tanvi says
Made this today for Christmas lunch! CMe out delicious! Thank you!
Alpa Jain says
Hi Tanvi,
Thankyou for the feedback.
Regards
Alpa
Athreya says
Delicious!
Alpa Jain says
Hi Athreya
Glad you liked it
Regards
Alpa
Rashi says
I tried it .. It was amzing,.. Thanks for sharing and images as well.. They are very helpful 🙂
Alpa Jain says
Hi Rashi
Thankyou for the feedback. Glad to know you liked it 🙂
Regards
Alpa
Mrs D says
Thanks for sharing this and breaking down how to make the white sauce. I’ll be trying this one out!
Lathiya says
The casserole loaded with veggies perfect for the weekend dinner.
Neecee B says
Love the pictures. Such great tips.
Ana Smith says
Yummy!
I love cheese, and I love vegetables and this combo looks rich and so inviting...