Cheesy Baked Chicken Parmesan Quinoa Casserole

Chicken Parmesan Quinoa Casserole is a comforting, protein-rich dinner the whole family will love. Tender, parmesan-crusted chicken breasts sit over a flavorful quinoa and marinara base filled with sautéed vegetables. This oven-baked, one-dish meal is simple to prepare, nutrient dense, and makes great leftovers—perfect for busy weeknights.

This casserole improves with each batch. Everything bakes together in one pan: quinoa, veggies, marinara, and a crispy parmesan coating on the chicken. It’s a satisfying, nutrient-dense meal with plenty of protein and fiber, and it’s flexible enough to adapt to dietary preferences.

What You Need for Chicken Parmesan Quinoa Casserole

The base combines white quinoa with sautéed vegetables—onion, green pepper, and mushrooms—for texture and flavor. The sauce blends marinara and broth with garlic and Italian seasoning. Chicken breasts are coated in a simple parmesan-and-flour mixture, dredged through egg, and baked on top of the quinoa mixture until golden and cooked through.

Why You’ll Love It

• High in protein and filling: about 57 g of protein per serving.
• One-dish, oven-baked convenience with minimal hands-on time.
• Freezer-friendly and great for feeding family or sharing with friends.

Variations

• Vegetarian: Swap chicken for thick slices of eggplant or large portobello mushrooms. Baking time stays similar.
• Gluten-free: Use a gluten-free all-purpose flour in the parmesan coating.
• Cheese swap: Mix shredded mozzarella with parmesan for a gooey topping.
• Extra veg: Add broccoli, zucchini, peas, or spinach to the quinoa mixture for more color and nutrients.

Ingredients (Serves 4)

• 2 tablespoons olive oil
• 1/2 large yellow onion, diced (~1/2 cup)
• 1 medium green pepper, diced
• 8 oz white mushrooms, diced
• 1.5 teaspoons sea salt, divided
• 3 cloves garlic, minced
• 1 tablespoon Italian (Tuscan) seasoning
• 1 cup white quinoa, rinsed
• 3 cups marinara sauce (about 24 oz)
• 1 cup chicken or vegetable broth
• 2.5 tablespoons all-purpose flour (or gluten-free all-purpose)
• 1.5 cups shredded parmesan cheese, plus extra for topping
• 2.5 teaspoons garlic powder
• 1/2 teaspoon freshly ground black pepper
• 1 large egg, beaten
• 1.5 lbs boneless, skinless chicken breasts (about 4 small breasts)

Instructions

1. Preheat the oven to 375°F (190°C). Spray or lightly oil a 9×13-inch casserole dish.
2. Heat the olive oil in a large skillet over medium-high heat. Add the diced onion and season with 1/4 teaspoon salt. Sauté 1–2 minutes until softening.
3. Add the green pepper, mushrooms, and minced garlic. Reduce heat to medium, add another 1/2 teaspoon salt and 1 tablespoon Italian seasoning. Sauté for 5–7 minutes until vegetables are tender. Remove from heat.
4. Combine the rinsed quinoa and sautéed vegetables in the prepared casserole dish. Pour in the marinara sauce and broth, then add the remaining salt. Toss to combine and wipe any sauce from the casserole edges to prevent burning. Cover the dish.
5. Bake the covered casserole for 30 minutes.
6. While the quinoa bakes, prepare the chicken: in a shallow bowl, mix the flour, 1.5 cups parmesan, garlic powder, and black pepper. In a separate bowl, beat the egg.
7. Dredge each chicken breast first in the beaten egg, letting excess drip off, then press into the parmesan-flour mixture so each breast is well coated. Add more flour/cheese to the bowl if needed to coat all pieces.
8. After the quinoa has baked 30 minutes, remove the dish from the oven and stir the quinoa mixture. Arrange the coated chicken breasts on top of the quinoa, cover again, and return to the oven for 20 minutes.
9. Uncover and bake an additional 10–15 minutes, until the chicken is golden and reaches an internal temperature of 165°F (74°C).
10. Remove from the oven and let the casserole rest 5 minutes before serving. Sprinkle additional shredded parmesan or fresh basil if desired.

Tips & Notes

• Pre-cooking the vegetables adds depth of flavor, but if you prefer fewer dishes you can add them directly to the casserole raw—results will still be tasty, though slightly different in texture.
• Oven temperatures vary, so check chicken doneness with a thermometer to ensure it reaches 165°F (74°C).
• This casserole freezes well. Cool completely, freeze in airtight containers, then thaw thoroughly in the refrigerator before reheating.

Nutrition (approx. per serving)

Calories: 552 kcal • Carbohydrates: 46 g • Protein: 57 g • Fat: 15 g • Fiber: 7 g • Sugar: 9 g

Nutrition information is an estimate and should be used as a guideline only.

Serving Suggestions

• Serve with a crisp green salad and a simple vinaigrette for a balanced meal.
• Finish with fresh basil, a drizzle of olive oil or balsamic glaze, or a sprinkle of red pepper flakes for extra flavor and color.

Storage

Store leftovers in an airtight container in the refrigerator for up to 3 days. For longer storage, freeze in portioned containers. Thaw in the refrigerator before reheating. Flavors often meld and improve after a day or two.

FAQ

• Can I use a different grain? Yes—rice could work with a similar liquid ratio, though we haven’t specifically tested other grains.
• How do I make it spicier? Add red pepper flakes to the marinara or include a pinch of cayenne in the parmesan coating.
• Can I use store-bought marinara? Absolutely. Homemade marinara brings extra flavor, but a quality store-bought sauce is a convenient option.

Photography by: The Wooden Skillet