Zucchini and Hamburger Casserole is a simple layered bake: salted zucchini rounds, lean ground beef cooked with onion, garlic, diced tomatoes and Italian seasoning, and two layers of melted mozzarella, all in an 8×8-inch dish. It takes about 15 minutes of prep and 25 minutes in the oven, plus a short wait for the zucchini and a 10-minute rest, and serves 6.
How to make it: Slice the zucchini into 1/2-inch rounds, salt them in a colander for 15 minutes, then rinse and pat them dry. Brown the beef with the onion and garlic until it reaches 160°F, and stir in the drained tomatoes and seasonings. Layer half the meat, half the zucchini and half the mozzarella, repeat, and bake at 350°F until the center reaches 165°F.
Why You’ll Love It
- Short ingredient list: zucchini, ground beef, a can of tomatoes, mozzarella and a few seasonings.
- No pasta to boil: the zucchini rounds take the place of noodles in the layers.
- Uses up zucchini: about 2 pounds go into one dish.
- Quick bake: 20 to 25 minutes in the oven.
Ingredient Notes
Zucchini: 2 medium zucchini, about 2 pounds, sliced into 1/2-inch rounds. You’ll also need some salt for salting them; it gets rinsed off before the zucchini goes in the dish.
Lean ground beef: 1 pound. If your beef isn’t lean, drain the fat after browning.
Onion and garlic: 1 small onion, diced, and 2 cloves of garlic, minced, cooked in 1 tablespoon of olive oil.
Diced tomatoes: one 28-ounce can, drained.
Seasonings: 2 teaspoons of Italian seasoning, 1/2 teaspoon of kosher salt and 1/2 teaspoon of black pepper.
Mozzarella: 2 cups, shredded, split between the two layers.
Ingredients
- 2 medium zucchini (about 2 pounds), sliced into 1/2-inch rounds
- Salt, for salting the zucchini (rinsed off before cooking)
- 1 tablespoon olive oil
- 1 small onion, diced
- 2 cloves garlic, minced
- 1 pound lean ground beef
- 2 teaspoons Italian seasoning
- 1/2 teaspoon kosher salt
- 1/2 teaspoon black pepper
- 1 can (28 ounces) diced tomatoes, drained
- 2 cups shredded mozzarella cheese
How to Make Zucchini and Hamburger Casserole
1. Salt the zucchini. Slice the zucchini into 1/2-inch rounds. Put the rounds in a sieve or colander over the sink or a bowl and sprinkle with salt, tossing to coat.
2. Let it sit. Let the salted zucchini sit for 15 minutes to draw out excess moisture.
3. Rinse and dry. Rinse the zucchini well under cold water to remove the excess salt, then pat it dry with paper towels.
4. Soften the onion. Heat the olive oil in a large skillet over medium-high heat. Add the onion and cook until it begins to soften, about 2 minutes.
5. Brown the beef. Add the garlic and ground beef, breaking the beef up with a spoon, and cook, stirring often, until it is browned with no trace of pink, about 5 minutes. Check that the beef reaches 160°F on a food thermometer.
6. Make the meat mixture. Stir in the drained tomatoes, Italian seasoning, kosher salt and black pepper. Remove the skillet from the heat.
7. Heat the oven. Heat the oven to 350°F.
8. Layer the casserole. In an 8×8-inch baking dish, spread half of the beef mixture. Cover it with half of the zucchini slices, then half of the mozzarella. Repeat with the rest of the beef mixture, zucchini and mozzarella.
9. Bake. Bake for 20 to 25 minutes, until the cheese is melted and beginning to brown and the center reaches 165°F on a food thermometer.
10. Rest and serve. Let the casserole rest for 10 minutes before serving.
Tips for the Best Zucchini Casserole
Zucchini holds a lot of water, so most of the work here is about getting some of it out before baking:
- Salt, rinse and dry the rounds. Fifteen minutes in a colander with salt draws out excess moisture. Rinse off the salt and pat the slices dry with paper towels.
- Drain the tomatoes. Pour off the liquid from the can before stirring them into the beef.
- Drain the fat. Lean beef usually doesn’t need it, but if you see fat in the pan after browning, spoon it off.
- Let it rest. Ten minutes out of the oven lets the juices thicken and makes it easier to cut.
- Use a thermometer. Brown meat and melted cheese are good signs, but the beef should reach 160°F in the skillet and the center of the casserole 165°F in the oven.
Other Ways to Prep the Zucchini
Salting is the method in this recipe, but you can also prep the zucchini these ways:
- Sauté first: cook half-moon slices in 1 tablespoon of olive oil with a little salt and pepper over medium-high heat for 3 to 6 minutes, until they start to soften.
- Simmer and drain: simmer the slices in boiling water for 3 minutes until just crisp-tender, then drain them on paper towels and let them cool.
- Raw on top: slice the zucchini thin, 1/8 to 1/4 inch, and lay the raw slices over the meat and cheese, then season and sprinkle with Parmesan.
What Can I Do With Ground Beef and Zucchini?
This layered bake is one of the easiest answers. The same pair also works in a few other ways:
- With pasta sauce: use a 24-ounce jar of pasta sauce plus a can of petite diced tomatoes, and bake in a 9×13-inch dish.
- With cottage cheese: stir 1 cup of cottage cheese into the meat sauce, top with mozzarella, zucchini rounds and Parmesan.
- With pasta: layer the beef and zucchini sauce over cooked pasta for a bigger bake.
Variations
- Other cheese: use an Italian cheese blend instead of mozzarella, or add 1/2 cup of grated Parmesan on top.
- Other meat: swap in ground turkey or bulk Italian sausage. Cook ground turkey to 165°F.
- Bell pepper: cook a small chopped green bell pepper with the beef.
Storage & Reheating
Refrigerator: Refrigerate leftovers within 2 hours (1 hour if the room is above 90°F) in shallow covered containers. They keep 3 to 4 days.
Freezer: Leftovers can be frozen for 3 to 4 months. Thaw them in the refrigerator, never on the counter.
Reheating: Reheat covered until the casserole reaches 165°F. From frozen, it takes about one and a half times as long. Don’t reheat leftovers in a slow cooker.
What to Serve With It
Serve it with garlic bread, or spoon it over pasta. For more ground beef bakes, try stuffed pepper casserole, beef Lombardi casserole, easy hamburger rice casserole or a bacon cheeseburger casserole. Still have zucchini left? Make skillet zucchini and mushrooms or baked zucchini fries.
Frequently Asked Questions
What are some tips for the best zucchini casserole?
Salt the zucchini rounds for 15 minutes, rinse and pat them dry, drain the tomatoes, and let the casserole rest 10 minutes before cutting.
What can I do with ground beef and zucchini?
Layer them with tomatoes and mozzarella in this casserole, bake them with pasta sauce and cottage cheese, or layer them over pasta.
What are the ingredients in a zucchini ground beef casserole?
Zucchini, lean ground beef, onion, garlic, olive oil, a can of diced tomatoes, Italian seasoning, salt, pepper and mozzarella.
Can I use a 9×13 dish?
This recipe is written for an 8×8-inch dish. A 9×13 also works with the same pound of beef, but the layers will be thinner, so check the center with a thermometer.
Final Notes
This is a good one for late summer, when zucchini piles up on the counter. If you try it with Italian sausage, tell me in the comments how you liked it.
Zucchini and Hamburger Casserole
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Ingredients
- 2 medium zucchini about 2 pounds, sliced into 1/2-inch rounds
- salt for salting the zucchini; rinsed off before cooking
- 1 tablespoon olive oil
- 1 small onion diced
- 2 cloves garlic minced
- 1 pound lean ground beef
- 2 teaspoons Italian seasoning
- 1/2 teaspoon kosher salt
- 1/2 teaspoon black pepper
- 1 can diced tomatoes 28 ounces, drained
- 2 cups shredded mozzarella cheese
Instructions
- Slice the zucchini into 1/2-inch rounds. Put the rounds in a sieve or colander over the sink or a bowl and sprinkle with salt, tossing to coat.
- Let the salted zucchini sit for 15 minutes to draw out excess moisture.
- Rinse the zucchini well under cold water to remove the excess salt, then pat it dry with paper towels.
- Heat the olive oil in a large skillet over medium-high heat. Add the onion and cook until it begins to soften, about 2 minutes.
- Add the garlic and ground beef, breaking the beef up with a spoon, and cook, stirring often, until it is browned with no trace of pink, about 5 minutes. Check that the beef reaches 160°F on a food thermometer.
- Stir in the drained tomatoes, Italian seasoning, kosher salt and black pepper. Remove the skillet from the heat.
- Heat the oven to 350°F.
- In an 8x8-inch baking dish, spread half of the beef mixture. Cover it with half of the zucchini slices, then half of the mozzarella. Repeat with the rest of the beef mixture, zucchini and mozzarella.
- Bake for 20 to 25 minutes, until the cheese is melted and beginning to brown and the center reaches 165°F on a food thermometer.
- Let the casserole rest for 10 minutes before serving.
