Baked Eggplant and Polenta Casserole

Make this Eggplant Polenta Casserole for a vegetarian lasagna-style dinner that uses polenta instead of noodles. Layers of eggplant, mushrooms, creamy ricotta and melted mozzarella create a hearty, flavorful meal the whole family will enjoy.

You only need about 15 minutes of active prep to assemble this casserole, and it makes a comforting weeknight dinner or a great dish to bring to a potluck.

💚 About This Recipe

This idea started as a twist on classic lasagna by replacing pasta sheets with slices of prepared polenta and layering roasted eggplant and mushrooms between cheesy, saucy layers. The polenta adds a soft, slightly sweet corn flavor that complements the vegetables and cheese without overpowering them. The result is a satisfying vegetarian casserole that’s easier to assemble than traditional lasagna because you skip boiling and handling lasagna noodles.

🧂 Ingredients Needed

• Eggplant — sliced into rounds; provides meaty texture and savory flavor.
• Prepared polenta — a tube of pre-cooked polenta sliced into rounds saves time.
• Ricotta cheese — for creamy layers that mimic lasagna ricotta.
• Parmesan cheese — adds salty, nutty depth.
• Egg — binds the ricotta mixture so the layers hold together.
• Sliced mushrooms — optional, for an earthy boost.
• Marinara sauce — tomato sauce adds acidity and classic lasagna flavor.
• Shredded mozzarella — melts into a golden, bubbly topping.

🔪 Instructions

1. Preheat the oven to 450°F (230°C). Slice the eggplant into rounds about 1/4 inch thick. Lightly spray or brush with olive oil and arrange on a baking sheet. Roast for 20–25 minutes until tender and lightly browned.
2. While the eggplant roasts, slice the tube of prepared polenta into rounds and set aside.
3. In a medium bowl combine the ricotta, grated Parmesan, and the egg. Stir until smooth and well blended.
4. Place the sliced mushrooms in a microwave-safe dish and heat on high for about 5 minutes, stirring halfway, until they soften. Alternatively, sauté them briefly in a skillet.
5. Once the eggplant is done, lower the oven temperature to 350°F (175°C).
6. Spread a layer of marinara sauce on the bottom of a 9×13-inch casserole dish. Arrange half of the polenta rounds over the sauce in a single layer.
7. Spoon half of the ricotta mixture over the polenta rounds and spread gently. Top with half of the roasted eggplant and half of the mushrooms.
8. Sprinkle with half of the shredded mozzarella and spoon half of the remaining marinara over that layer.
9. Repeat the layers with the remaining polenta, ricotta mixture, eggplant, mushrooms, and sauce.
10. Cover the dish with foil and bake for 30 minutes. Remove the foil, add the remaining mozzarella, and bake for an additional 12–15 minutes until the cheese is melted and bubbly and the casserole is heated through.

❔ FAQs

💭 Expert Tips and Tricks

• Slice eggplant evenly so pieces roast at the same rate. Thinner slices will cook faster.
• Arrange eggplant slices in a single layer on the baking sheet to brown evenly. Use only a light coating of oil.
• Avoid adding too much sauce to prevent a soggy casserole; just enough to flavor the layers is ideal.

📌 This eggplant polenta lasagna offers a delicious alternative to classic lasagna with extra vegetable nutrition and an easy assembly. It’s a crowd-pleasing, family-friendly meal.

💡 Substitutions and Variations

• Omit the mushrooms if you prefer or replace them with spinach, zucchini, or roasted peppers.
• Add Italian seasoning, garlic, or a pinch of red pepper flakes to the sauce for more depth.
• Swap ricotta for mascarpone, cottage cheese, or a blend of cream cheese and Greek yogurt for different textures; ricotta gives the most traditional lasagna flavor.
• Increase or change the cheeses—more mozzarella or a sprinkle of fontina or provolone works well.

🥫 Storage and Reheating

Store leftovers covered in the refrigerator in an airtight container for 3–4 days. You can freeze portions or an entire assembled casserole; thaw in the fridge before reheating. Reheat covered in the oven at 350°F until warmed through, or microwave individual portions.

🍴 What To Serve With This Dish

Serve the casserole with a simple green salad, roasted vegetables, or steamed greens. Garlic bread or crusty bread makes a great accompaniment for scooping up extra sauce and cheese.

✔️ More Casserole Recipes You’ll Love

• Corn Dog Casserole — a playful, family-friendly comfort dish.
• Cheesy Tater Tot Casserole — great for brunch or a cozy dinner.
• Crock Pot French Toast Casserole — a make-ahead breakfast favorite.
• Cowboy Cornbread Casserole — hearty, savory, and inspired by Southwestern flavors.

Vegetarian Polenta Lasagna

If you try this recipe, I’d love to see a photo—share it on social media and tag the recipe name so others can enjoy it too.

📋 Recipe Card

Update Notes: This post was originally published in July 2014 and updated with new tips, photos, and a recipe revision in June 2023.