If you’re looking for an easy and nourishing recipe that the whole family will love, whip up this Italian-inspired ground beef and zucchini casserole for dinner! Made with a veggie-loaded hamburger and quinoa base that’s smothered in tomato sauce and topped with cooked zucchini, it’s filling, flavorful, and healthy. Put your late-summer zucchini to good use with this high-protein and gluten-free fan favorite!
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Dietitian Lizzie’s Notes
If you’re swimming in summer’s most prolific vegetable and looking to make something other than your 900th loaf of zucchini bread, I have the perfect savory zucchini recipe for you! It also happens to come in casserole form, which is so convenient for busy back-to-school evenings.
I’ve always been a fan of zucchini combined with tomato sauce, and that winning pair is what inspired this ground beef zucchini casserole recipe. It’s loaded with veggies and a healthier-for-you carbohydrate (hi, quinoa) in addition to tons of protein from the ground beef and cheese. This combo of ingredients provides a balance of nutrients that will keep you satisfied and stabilize blood sugar without being too indulgent or high in calories. As such, this meal is an excellent option for people with type 2 diabetes or anyone watching what they eat.
Not to mention, the creamy combo of ricotta and mozzarella makes it delightful to eat and provides lasagna-esque vibes. (See my Beef and Spinach Lasagna if you actually want that.) A meal that tastes like comfort food but still delivers nutritional value is always a win in my book!
5-Star Review
Delicious! I used Yves veggie ground round instead of ground beef, and we all loved it. A real comfort food!”
– Katie
Ingredients and Substitutions
- Quinoa: You’ll need about 3 cups cooked (1 cup dry). Feel free to sub another cooked whole grain, such as brown rice or farro, or even cooked short cut pasta like orzo (if you don’t need it to be gluten-free).
- Ground beef: Use 85/15 or 90/10 lean ground beef for best results. Since these are leaner varieties, you won’t have to drain the ground beef before adding it to the casserole. If you use 80/20 beef, you should drain it to prevent the meal from getting too greasy. Consider using ground turkey or Italian sausage for a different flavor profile if desired.
- Yellow onion, carrots, and minced garlic: These are cooked with the ground beef to add flavor, texture, and nutrition. Sub a teaspoon of garlic powder if you don’t have fresh.
- Zucchini: Regular zucchini, yellow squash, or patty pan squash would all work. Even frozen zucchini does well in ground beef zucchini casserole.
- Marinara sauce: Zucchini with ground beef and tomato sauce is a seriously winning combo, but the end flavor highly depends on the type of sauce you use, in my opinion. I love to use Rao’s brand for this recipe! My Canned San Marzano Tomato Sauce or Fresh Tomato Sauce would also be delicious in here. If you don’t have any tomato sauce, sub diced tomatoes and add a teaspoon of Italian seasoning.
- Ricotta and mozzarella cheese: Sub cottage cheese for ricotta if that’s what you have. I like to use whole milk ricotta for maximum creaminess, but any fat content will work. Use pre-shredded mozzarella for ease, or you can pull apart a log of fresh mozzarella.
- Basil: It’s pretty convenient that zucchini season also happens to be when fresh basil is abundant! It’s the perfect garnish, but feel free to skip it if you don’t have any.
- Salt, pepper, and olive oil
How to Make Ground Beef Zucchini Casserole
The full recipe card with ingredient amounts and instructions is at the bottom of the post. Here’s a preview of the steps with photos to guide you in the kitchen.
Cook the quinoa according to package instructions until tender and fluffy.
In a large skillet, cook onions and carrots in olive oil until softened.
Add the ground beef, garlic, and salt to the skillet. Cook, breaking up the beef as you go, until the beef is browned.
Transfer the veggie and beef mixture to a greased 9×13″ baking dish or casserole dish.
Add the cooked quinoa to the mixture.
Stir in the ricotta and half of the mozzarella cheese.
Add two cups of the marinara sauce.
Stir until everything is combined. The dish will be very full.
Place the sliced zucchini in the same skillet used for the beef mixture. Add some additional olive oil if needed. Cook, stirring occasionally, until the zucchini is softened and lightly browned.
Spoon the zucchini pieces on top of the casserole to create a top layer. Pour the remaining marinara sauce on top.
Sprinkle the remaining shredded cheese on top.
Bake in the preheated oven (set to 375 degrees F/190 degrees C) until the cheese is melted and lightly browned. The edges should be bubbling. Garnish with fresh basil!
Top Tip
The zucchini must be sautéed before adding it to the casserole, since the cooking process draws out excess moisture. This prevents the zucchini casserole from getting watery.
Customize It
- Add more veggies. Add some chopped mushrooms either in addition to or in place of part of the ground beef. Celery and bell peppers are always a welcome addition, too. Stir in a handful of baby spinach for some greens.
- Change up the seasonings. For a kick, add ½ teaspoon red pepper flakes at the same time as the garlic and salt. You can also add ½ to 1 teaspoon of dried Italian seasoning for a flavor boost.
- Make it vegetarian. Readers have had success swapping in ground beef substitutes, including Yves grand round and Beyond Meat plant-based ground beef.
- Try different cheeses. Cottage cheese adds a salty kick and protein boost when used in place of ricotta cheese. It’s also a more affordable option. Swap in parmesan for half of the mozzarella for a different flavor.
What to Serve With It
Zucchini ground beef casserole is a nutritionally balanced main dish on its own, but you can of course add a side if desired. I love serving it with garlic bread and/or a simple mixed greens salad. It would pair well with my Simple Spinach Arugula Salad.
Storing, Freezing, and Make-Ahead
- Fridge storage: Leftovers will last in an airtight container in the fridge for up to 3 to 5 days. Reheat in the microwave in 30-second intervals on high, stirring in between, until warmed through. If you have a significant amount of the casserole left after initially baking it, consider keeping it covered in the baking dish in the fridge and reheating the whole thing in the oven. Reheat covered with foil for about 20 to 25 minutes at 375 degrees F.
- Making in advance: If you want to make ground beef and zucchini casserole ahead of time, assemble everything in the casserole dish and keep it covered in the refrigerator for up to 24 hours. Leave at room temperature while you preheat the oven, then pop it in and enjoy!
- Freezing the whole casserole: Let the casserole cool completely after baking. Wrap the entire pan in a tight layer of plastic wrap followed by a layer of aluminum foil. Freeze for up to 3 months. Be sure to use a dish that can be frozen. I like using this Oxo casserole dish (that also comes with a handy lid so you can skip the plastic wrap and foil).
- Reheating from frozen: Let the casserole thaw overnight in the fridge, remove the plastic wrap and foil, re-cover it with foil, and bake at 375 degrees F for 25 to 30 minutes.
- Freezing and reheating individual portions: You can also divide the casserole into individual portions after baking and cooling. This is a great meal prep option! Transfer the portions to individual bags or freezer-safe containers, such as Souper Cubes. Freeze for up to 3 months. Thaw overnight in the fridge. Reheat in the microwave in 30-second intervals on high until warmed through.
More Zucchini Recipes
- Vegetable Lasagna with White Sauce
- Zucchini Pizza Boats (with Topping Ideas!)
- Vegetarian Enchiladas Verdes with Zucchini
- Sweet Potato and Zucchini Fritters (Vegan)
- Zucchini Risotto with Shrimp
📖 Recipe
Ground Beef Zucchini Casserole
Equipment
- 3 quart (13×9) baking dish
Ingredients
- 3 cups cooked quinoa - from 1 cup dry
- 2 tablespoons extra virgin olive oil - divided
- 1 small sweet onion - diced
- 1 large carrot - diced
- 2 cloves garlic - minced
- 1 pound ground beef - use 90/10 or 85/15 to avoid it being greasy
- ½ teaspoon kosher salt
- ¼ teaspoon freshly ground black pepper - more to taste
- 1 pound zucchini - about 1 medium, cut into ¼-inch thick half-moon pieces
- 1 cup ricotta cheese - can sub cottage cheese
- 1.5 cups shredded mozzarella cheese
- 24 ounces marinara sauce - I love Rao's brand
- 2 tablespoons chopped fresh basil - plus more leaves for garnish if desired
Instructions
- Preheat the oven to 375℉/190℃. Grease or spray a 13×9 (3 quart) baking dish with butter or oil. Set aside.
- If you need to cook the quinoa, do so first. Combine 1 cup dry quinoa with 2 cups of water or broth in a saucepan. Bring to a boil, cover, and simmer for about 15 minutes until the water is absorbed. Remove from heat and fluff with a fork.
- In a large skillet, warm 1 tablespoon of the olive oil over medium heat. Add the onion and carrot. Cook for about 5 minutes until they start to soften.
- Add the garlic, ground beef, and salt. Break up the beef with a spoon as it cooks. Cook for about 7 to 9 minutes, stirring occasionally, until the beef is browned and cooked through and the veggies are tender. Remove from heat. Add additional salt and pepper to taste.
- Transfer the cooked quinoa and veggie and beef mixture to the prepared casserole dish.
- Stir in all of the ricotta cheese, 1 cup of the mozzarella, and 2 cups of the marinara sauce. The dish will be very full.
- In the same skillet that you used for the beef and veggies, warm the other tablespoon of olive oil (you may not need it if there’s still some grease in there). Add the zucchini and cook for 5 to 7 minutes, stirring occasionally, until lightly browned and softened.
- Layer the cooked zucchini on top of the mixture in the dish.
- Pour the rest of the sauce on top. Sprinkle with the remaining mozzarella cheese.
- Bake for 25 to 30 minutes until the cheese is melted and lightly browned and the edges are bubbling. If desired, you can flip the oven to the broil setting at the end and cook for 1 to 2 minutes to toast the cheese on top a little more.
- Garnish with fresh basil, serve warm, and enjoy!
- Leave a rating or review by tapping the stars on this recipe card (above) or in the comments section (at the end of the post)!
Notes
- Keep leftovers in an airtight container in the refrigerator for up to 3 to 5 days. Reheat in the microwave in 30-second intervals, stirring in between, until warmed through.
- To make ahead of time, assemble the casserole, cover with foil, and keep in the fridge for up to 24 hours before baking.
- To freeze, let the casserole cool completely. Wrap the entire pan in plastic wrap followed by aluminum foil. Freeze for up to 3 months. Thaw the casserole in the fridge overnight. Remove the plastic wrap and foil, then re-cover with foil to prevent the cheese from getting too brown. Bake at 375 degrees F for 25 to 30 minutes until warmed through.
Katie
Delicious! I used Yves veggie ground round instead of ground beef and we all loved it. A real comfort food!
Lizzie Streit, MS, RDN
Yum! I’m so glad you enjoyed it and that it worked well with the veggie ground round!
Brenda P
This is a vegetarian site is it not??? Why are you advertising beef in this recipie. I read through the recipe to see if you had veggie ground in it, but no you didn’t put in a substitution fur the beef. While I can easily substitute veggie ground round myself, or lentils, I was disappointed that beef was in the title of a vegetarian site.
Lizzie Streit, MS, RDN
This is not a vegetarian site. Many recipes are vegetarian but several include meat and fish. The recipes I create are veggie-loaded and do not fit any particular diet label. This is clearly indicated on my site’s about page as well as several other areas on the site. Anyone is welcome to modify the recipes as they wish.