Roasted Vegetable and Polenta Casserole for Rich Wholesome Flavor

When I returned home from a trip to Seattle over the Summer, I had a delicious surprise waiting for me. My boyfriend had made a roasted vegetable and polenta casserole. I've had polenta many times before, but never his and never as a casserole loaded with veggies. I was in heaven.

He didn't have a recipe for it so I knew that I'd be coming up with one so I could share it with you. It's such a wholesome dish—I imagine it will be a core meal in my home this winter.

One recommendation... Switch out the veggies for what's seasonal and local vegetables whenever you can. This will keep your taste buds very happy!

Roasted Vegetable and Polenta Casserole

By Chef Katie Mae, Inspired by Mr. Ben Hampton
Makes 4 servings | Ready in 60 minutes | Stores 1 week in fridge


  • 5 cups water
  • 1 cup coarsely-ground cornmeal or polenta*
  • 1 cup low-sodium vegetable broth or water
  • 1 zucchini, ½-inch slices on the diagonal
  • 1 yellow squash, ½-inch slices on the diagonal
  • 1 onion, thinly sliced
  • 10 crimini mushrooms, thinly sliced (about 1 cup)
  • 2 Roma tomatoes, sliced thinly
  • ½ tablespoon garlic granules
  • ½ tablespoon of salt-free seasoning
  • ½ tablespoon of dried oregano or thyme
  • 2 cups unsweetened tomato sauce



  1. Bring the water to a boil in a large saucepan over medium heat.
  2. Preheat the oven to 400°F. Line a rimmed baking sheet with parchment paper and set aside.
  3. Pour the cornmeal into the boiling water, whisking it as you pour. Turn down the heat and continue to whisk until the cornmeal has thickened enough that it doesn’t settle to the bottom of the pan when the stirring stops.
  4. Cover and continue to cook the polenta for 30 minutes. Whisk it well every 5 minutes to avoid clumping. Make sure to scrape the bottom and sides of the pan to prevent sticking.
  5. Add the sliced veggies to the prepared baking sheet and spread out. Carefully pour the vegetable broth over the vegetables. Sprinkle with garlic, herbs, and no-salt seasoning.
  6. Cover with foil and bake for 20 minutes. When they’re done, set aside until needed.
  7. Once the polenta has a creamy, porridge-like consistency, pour it into a 9x12-inch casserole dish (a pie pan also works). Top with slices of tomato and bake for 10 minutes.
  8. Then remove the polenta from the oven and layer on the roasted veggies. Lastly, gently pouring the tomato sauce over the casserole and bake for 10 more minutes.
  9. Let the finished casserole cool for 10 minutes before slicing and serving.



Polenta is actually a dish from northern Italy, not an ingredient. Polenta is a porridge that is made from coarsely ground cornmeal. If you see a package labeled polenta it may be the prepared dish, but most often it means that the grind of the corn is appropriate to make the polenta dish. In this recipe you can use medium ground cornmeal, coarsely ground cornmeal, or a polenta product like mentioned. Do not use finely ground cornmeal or corn flour, which will lead to the finished dish having pasty texture.


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