Vegetable Polenta Casserole

$5.87 recipe / $0.98 serving

Someone asked me the other day if I ever cook anything that just doesn’t turn out well and the answer is YES. If I ever go more than a few days without posting a recipe, there’s a good chance that whatever I cooked just didn’t turn out well and I have to wait for my next day off to try again. But a lot of times I’m never really sure how I feel about a recipe until I eat the leftovers for lunch the next day. Then it’s crystal clear whether I’ve got a hit or miss.

That’s what happened with this gem. When I cooked it, I was a little disappointed with the visual appeal of the final product and was so distracted by other stuff going on that I just couldn’t get into eating it. The next day I brought it to work for lunch and I fell in love! I ate it every day for lunch after that and just couldn’t get enough!

The casserole combines a base of polenta (cornmeal) cooked in vegetable broth and with frozen spinach mixed right in. Next, I sautéed some veggies, added diced tomatoes and herbs to make a quick sauce, and layered that on top of the cooked polenta. I added a touch of shredded mozzarella on top for good measure and baked it all until it was hot and bubbly. The end result reminded me a little of lasagna, but vegetarian and gluten free. The texture is soft, but the flavor is spot on!

I’ll definitely be trying different variations on this recipe and I plan to test out a different broth to cornmeal ratio to help solidify the bottom layer. Buying coarse ground cornmeal (like true polenta) may also help thicken the bottom layer (I just used regular, finely ground cornmeal). Either way, it still tastes awesome and I want MORE!

P.S. I went kind of large on the serving sizes here, because let’s be honest. Cornmeal and vegetables isn’t terribly filling.

Vegetable Polenta Casserole

Vegetable Polenta Casserole - Budget Bytes

4.9 from 7 reviews

Vegetable Polenta Casserole
Prep time
Cook time
Total time
Total Cost: $5.87
Cost Per Serving: $0.98
Serves: 6
  • 3 cups vegetable broth $0.39*
  • 1 cup cornmeal $0.24
  • 8 oz. frozen chopped spinach $0.78
  • 2 Tbsp olive oil $0.32
  • 2 cloves garlic $0.16
  • 1 small onion $0.50
  • 1 small zucchini $0.58
  • 1 small yellow squash $0.76
  • 1 (15 oz.) diced tomatoes $0.69
  • ½ tsp basil $0.05
  • ½ tsp oregano $0.05
  • ½ tsp smoked paprika $0.05
  • freshly ground black pepper (10-15 cranks of a mill) $0.05
  • 4 oz. (1 cup) shredded mozzarella $1.25
  1. Bring the vegetable broth to a rolling boil in a medium sauce pot. Stir together the cornmeal plus one cup of water to make a slurry, then stir it into the boiling water (this helps reduce clumps). Reduce the heat and let it simmer for 10-15, or until thickened. Once thickened, stir in the frozen spinach until heated through.
  2. Meanwhile, mince the garlic and dice the onion, zucchini, and squash. Combine the onion, garlic, and olive oil in a large skillet and sauté over medium heat until the onions are softened. Add the zucchini and squash and sauté about five minutes more.
  3. Once the zucchini and squash are soft, add the tomatoes, basil, oregano, paprika, and pepper. Stir to combine and let simmer for about 10 minutes. Begin to preheat the oven to 350 degrees.
  4. When the cornmeal (polenta) is finished cooking, pour it into the bottom of an 8×8 inch casserole dish. After the vegetable mixture has finished simmering, spread it on top of the polenta in the casserole dish. Top with the shredded mozzarella.
  5. Bake the casserole for about 20-25 minutes, or until it is heated through and the cheese is bubbly on top. Serve hot.
*I use Better Than Bouillon reconstituted with water to make my broth. It’s much less expensive than canned or boxed broths.


Vegetable Polenta Casserole - Budget Bytes


Step by Step Photos

Cornmeal Mush

Cook one cup of cornmeal according to the package directions, using 3 cups of vegetable broth in place of the three cups of boiling water.


Once the cornmeal (polenta) has thickened, add 8 oz. (1/2 lb) of frozen, chopped spinach. The kind that is frozen loose in a bag as opposed to a block works best here because you can just stir it into the polenta straight from the freezer.

Layer One

Spread the polenta-spinach mixture into the bottom of an 8×8 casserole dish.

Onions and Garlic

While the polenta is cooking, mince the garlic and dice the onion, zucchini, and yellow squash. Add the onion and garlic to a skillet with the olive oil and sauté over medium heat.


Once the onions are soft, add the squash and zucchini. Sauté for a few minutes more, or until the squash begin to soften.

Tomatoes and Herbs

Next, add on 15oz. can of diced tomatoes, 1/2 tsp basil, 1/2 tsp oregano, 1/2 tsp paprika, and some freshly cracked pepper. Stir to combine and let this mixture simmer for about 10 minutes. Also, begin to preheat the oven to 350 degrees.

Lyer Two

After the mixture has simmered, spread it out over the polenta in the casserole dish.


Lastly, add 4 oz. (1 cup) shredded mozzarella cheese. bake the casserole in the preheated oven for 20-25 minutes, or until it’s heated through and the cheese is bubbly on top. I went light on the cheese because I’m trying to cut back, but you could certainly add more, or add a layer of ricotta!

Baked Vegetable Polenta Casserole

And then when it’s finished baking it’s beautiful and it smells delicious! Now, when it first comes out of the oven, the polenta is very soft so the whole thing just kind of mushes together… after cooling in the refrigerator it firmed up and I was able to scoop proper portions into smaller containers.

Vegetable Polenta Casserole - Budget Bytes

Like lasagna… ‘cept different.


  1. Katie says:

    You have such perfect timing! I was planning my recipes for the week, and I already have over half the ingredients! Can’t wait to try it. Thanks for the great recipes.

  2. Yes please! I have kind of a lot of cornmeal lying around and I rarely know what to do with it (besides make cornbread, of course), but now I have big plans! BIG plans. :) I bet this would be great with a drained can of chickpeas added to the veg layer for extra protein too!

  3. Lisa Shaw says:

    I don’t even like squash of any kind but I do believe I would eat this and like it, yes I would. It looks delicious! :-)

  4. Linda Westphal says:

    I mashed in cooked sweet potato the last time I made polenta. Delicious! Added texture, flavor and vitamins.

  5. Mary says:

    Hiya Beth. This is looking reeeeeal good. I can’t have dairy anymore though. Do you think this would still taste good without the cheese?

    • Well, the cheese definitely gives it more body. It will still have a lot of flavor, it will just be a bit less filling. Maybe add some beans? White beans in with the vegetables?

      • I’m going to sub homemade tofu ricotta for the mozz!

        • Rebecca says:

          I made it without the cheese (replaced the yellow squash with mushrooms and topped it with some grilled eggplant) and it was delicious! Was plenty filling for me.

  6. Nancy says:

    This looks yummy and easy and I have almost everything on hand. Think I’d be okay swapping out eggplant for the zucchini? And maybe add some peppers?

  7. Looks great! If you want the polenta to get harder, you might try leaving it uncovered at room temperature for about an hour and only after that add the vegetables on top and cook again, for me it helped in the past with other polenta recipes.

    • pat cincotta says:

      I was going to comment that this dish came out very soft and was mixed together. I wanted it to be firm on the bottom with the vegetables like a topping. Second time, I baked the polenta for a short time and then let it cool before adding the vegetables and tomatoes. It was solid enough that I could turn the pan sideways and the polenta stayed firm. It worked out great. Delicious.

  8. A layer of breadcrumbs on top might give it more substance and crunch as well. Or maybe stirring in some pine nuts?

  9. Beth, would red peppers and mushrooms be fine with this you think?

  10. Yolanda says:

    Hi Beth,

    How do you think pre-cooked Polenta would fare in this recipe? The kind sold in chubs (like sausage)?
    I’m thinking I could layer the frozen spinach on top of that, but I’m worried it would make the polenta soggy.

    • I think that would work well and I actually think the pre-cooked kind would be less soggy than mine was. You can cut it into rounds and then just layer them in the bottom. The frozen spinach in a bag doesn’t have nearly as much water as the kind frozen into a block, so I think it will be okay.

  11. Mary Kathryn says:

    How do you think masa flour (very finely ground cornmeal) would work in this recipe? I have a huge bag of masa, but no cornmeal, and this looks wonderful! I have made cornbread with it before, so I think it should work with just a little more liquid than the original recipe calls for. Thoughts?

  12. Heather says:

    This hit the spot. I made a Spicy Shrimp version: added shrimp, mushrooms, two jalapenos, one red pepper, and smoked cheddar cheese. I had to drain the water out of the veggies before topping the polenta but it came out awesome. Topped with some avocado, plain yogurt and hot sauce and I went to TOWN.
    (Since I became pregnant I’ve wanted hot sauce, avocado and yogurt/sour cream on almost everything :)

  13. I love the idea of this! I’m a big fan of Bob’s Red Mill even though it’s just a bit more expensive. I’m going to try this and I guarantee that my wife and I will love it. However, I’ll do it as grits rather than polenta. (yeah, they’re one and the same–except grits is usually a side dish and polenta a “bed”).

  14. Try adding a few ounces of goat cheese to your polenta. It may change your life.

  15. No shade, but how is 4oz of cheese equal to 1 cup? I thought 1 cup is 8oz? Is it different with cheese?

    • Yes, it’s the difference between weight ounces and fluid (or volume) ounces. 8 fluid (or volume) ounces does equal one cup and this is usually used to measure liquids and semi-solids. With cheese, 4 oz. weight is about 1 cup in volume once shredded. :) Those bags of pre-shredded cheese that you buy in the store are two cups in volume, but 8 oz. in weight. I bought an 8 oz. (weight) bar of cheese and shredded it. Half of the bar was about one cup in volume once shredded (not packed tight).

  16. Mike says:

    I wonder, would baby spinach work in lieu of frozen? Just added a bit at a time to the polenta until it wilts? The only kind of frozen spinach I can get around here is in blocks and it’s such a pain to squeeze all the moisture out of it.

    When I get around to trying this I might add some grilled chicken too.

  17. Ethyn says:

    This sounds perfect for my toddler who loves veggies; can you suggest a way to add meat? This way my husband will eat it too:)

    • Maybe if you use some shredded rotisserie chicken meat and add it to the vegetable mix?

      • I think ground Italian sausage would also be delish!

        • Chandlee says:

          I totally agree, Anne! Cooking meat never ends well for me if I’m trying to improvise, though, so I’m just going to have some spicy Italian sausage as a side when I try this tomorrow.

  18. This looks like such a delicious veggie dish! Thanks a lot, pinning!

  19. I too have been one wondering about the site!! I was so sad not being able to access it as your site has become my go to. Love it. Congrats and looking forward to the book! (Will it be available on ibooks? I saw you will have a Kindle version..)
    I am so happy about this recipe in particular, I have a bag of yellow cornmeal needing to be used. (An almost casualty if another recipe attempt from another source gone awry.) Polenta sounds delish!!

  20. Hey Beth, do you think it’s possible to freeze this recipe? Would you recommend before or after baking it? Thanks!

    • Yes, I think this would freeze very well! I think you could freeze it either before or after baking, depending on whether you want to freeze single serving sizes (after baking) or the whole casserole (before baking). Everything is already cooked before it goes into the oven, so the baking part only really helps solidify things, makes sure it’s heated through, and melts the cheese. If you are going to freeze single serving portions, the microwave can do that job for you when you reheat it to eat. :)

  21. Looks incredible! I can’t wait to try it. I love polenta.

  22. Raissomat says:

    Awwww that looks alot like wat my mum used to make us..we grew our own corn and my mum actually calls them “polenta fields” to this day.
    The dish is called polenta-pizza in our house.
    I miss my mum.
    Polenta makes you (me) so nostalgic..

  23. Robyn says:

    Hi, Just wanted to say your book arrived today! Snowing like crazy all day and the UPS guy came through! Can’t wait to look at it tonight:):) Love your website!

  24. Hi Beth —

    Made this last night with fresh spinach — it was wonderful! The only addition I made was a sprinkling of Parmesan cheese on top of the mozz. cheese before baking.

    Thanks for the great recipe!

    p.s. I also love all the ideas in the comments… maybe will add sausage and mushrooms to the mix next time around…

  25. Lisa says:

    You had me at polenta! Yummmmm!

  26. Autumn says:

    Yummy Yummy!! We had enough for dinner for my hubby and I , lunch for me , and even a little extra! My ten month loved it too :)

  27. Made this last night in a 9×13 baking dish because I don’t have an 8×8 dish that was tall enough (my fillings would have overflowed). Anyway, I substituted the veg & cheese based on what I had in my fridge and also added some parmesan cheese into the polenta before I poured it in the bottom. It was delicious! Thanks for the great recipe :)

  28. Laura says:

    Oh my gosh I was going to make a similar polenta casserole tonight and I saw this and a light shone down on me “put spinach IN the polenta” why didn’t I think of that?!! And I have half a bag of spinach I was afraid would go bad soon! Woo! As usual, you’re amazing. Been reading your blog for YEARS and I don’t tell you his enough!

  29. Michelle says:

    This looks good. I may add red lentils to the polenta to add protein and bulk. They cook down pretty soupy (and quick) compared to green lentils.

  30. Jennifer N. says:

    This was wonderful! My polenta came out darker because I used “kitchen basics” brand veggie stock. I also added mushrooms to the veggie mix (because I had them in the fridge). Next time, I’ll add some smoked paprika to the polenta.

  31. I made this last night- with some mods. I added pumpkin puree to the spinach/polenta mix, then hand blended so make it super smooth.

    For the veg topping, I used a bag of frozen squash and onions and garlic, adding fresh basil.

    This is a super versatile recipe. Very delicious

  32. Oh this looks gorgeous too! Thank you!

  33. Amandie says:

    This was delicious!!! My first time ever having had and making polenta and I liked it! Bht I’m with you on adjusting the ratios to help solidify the polenta crust. I only had zucchini on hand so I added mushrooms and green peppers as well as garlic and onions. After all vegetables were finished cooking, I threw in some tomato paste. Flavor was awesome. Thanks so much!!!

  34. Lindsay says:

    I feel like I missed something… My polenta is still really soupy after 20 minutes :/

  35. Rebecca says:

    Just a note since you mention you use Better Than Bouillon for your broth… we save our veggie scraps to make broth and then it’s free, and comes out different every time.

  36. Erin says:

    Yum! Made this tonight, but with a couple substitutions. Since I was out of canned tomatoes, I subbed half a jar of marinara sauce. I also cooked the polenta in chicken broth and added a knob of butter at the end, before the spinach step. I ADORE polenta, and this is such a tasty way to eat it.

  37. Melissa says:

    Absolutely amazing! Thank you for sharing this recipe :). We omitted the vegetable broth to reduce the salt content of the dish, but I added a little cheese and some garlic and seasonings to the polenta/spinach mixture–and the casserole was just fabulous! Yay! A new, yummy meal–vegetarian, too.

Speak Your Mind


Rate this recipe: