Big Mac Casserole

Ingredients & Substitutions

Here I explain the best ingredients for my Big Mac casserole recipe, what each one does, and substitution options. For measurements, see the recipe card.

Zucchini Layer:

• Zucchini – I layer roasted zucchini on the bottom so it’s not just a pile of meat. I’ve also made this with roasted cauliflower, broccoli, and even bell peppers. Just make sure whatever veggie you use is cooked first so the casserole doesn’t get watery. If you want something heartier, sweet potatoes, regular potatoes, or other root veggies totally work too.
• Olive Oil – I use this to roast the zucchini so it gets a little caramelized and not mushy. Avocado oil works just as well if that’s what you have on hand.
• Sea Salt

Meat Layer:

• Ground Beef – I like using grass-fed beef because it has the best flavor and a little extra nutrition. My go-to is 85/15, which gives enough richness without being greasy. You can also make a Big Mac casserole with ground chicken or ground turkey. It’s just a bit lighter, but still super flavorful once you add the sauce and toppings.
• Onion – I usually go for white onion since it’s classic for that Big Mac flavor, but yellow or red onion work just fine too
• Olive Oil – Or avocado oil.
• Sea Salt & Black Pepper

Assembly:

• Thousand Island Dressing – This is the Big Mac sauce, so don’t skip it! You can buy it pre-made, but most store-bought versions have added sugar, so I like to mix up my own. I usually use my homemade thousand island dressing, but my NEW Big Mac sauce recipe works here too (It’s the one I use in my Big Mac bowl).
• Shredded cheese – I use cheddar because it melts well and tastes great with the beef, but honestly, any shredded cheese you like will work. Monterey jack, Colby, or even a cheddar blend are all good options for this Big Mac casserole.

Big Mac Casserole Toppings:

• Lettuce – I prefer iceberg cut from a head because it’s extra crisp, but pre-shredded works too. You can also use any other lettuce you like here.
• Tomato – Roma tomatoes are my go-to because they’re less watery, but honestly, any ripe tomato will do the trick.
• Pickles – I slice them into little circles for that classic Big Mac look. Just make sure you’re using dill pickles without added sugar or try making your own! I’ve also used diced asparagus pickles before for a fun twist.
• Thousand island dressing – Just drizzle a little more over the top before serving. It ties everything together.
• Sesame Seeds – Totally optional, but I love sprinkling these on top! It gives the whole thing that “burger bun” vibe without the actual bun.

How To Make A Big Mac Casserole

I have step-by-step photos here to help you visualize the recipe. For full instructions with amounts and temperatures, see the recipe card.

1. Roast zucchini. Spread the zucchini slices out in a single layer on a baking sheet. Brush them with oil and sprinkle with sea salt. Pop them in the oven and roast until they’re nice and tender.
2. Cook beef and onion. Heat the oil in a large skillet, add the beef, and season with salt and pepper. Cook until browned and most of the liquid is gone. Then, stir in the onion and cook until soft. I like a little browning for extra flavor, but translucent is fine too.

3. Assemble. Layer the zucchini in the bottom of a baking dish, slightly overlapping. Spread on the dressing, then add the beef and sprinkle with cheese.
4. Bake. Pop the Big Mac casserole into the oven until everything’s hot and the cheese is nice and melty.
5. Add toppings. Add the lettuce, tomato, and pickles. Drizzle with more dressing and finish with a sprinkle of sesame seeds.

More Ground Beef Casserole Recipes

If you’ve got more ground beef to use up, here are a few other casseroles I think you’ll love:

Ground Beef Casserole

Mexican Casserole

Cabbage Roll Casserole

Cheeseburger Casserole