Low carb or not, everyone loves this keto big mac casserole recipe! And what’s not to love? Layers of roasted zucchini, seasoned ground beef, plenty of cheese and keto thousand island dressing, and of course, fresh toppings. Tastes just like your favorite burger… without the carbs. I don’t really eat fast food anymore, but if you get a burger craving when you’re out and about, don’t miss my best keto fast food guide to find low carb choices just about anywhere. And, what I do still love is making healthier fast food re-makes at home! Big Mac salad has been popular on the blog for years, but you may also like a burger in a bowl or classic cheeseburger casserole.

What Is Big Mac Casserole?

This easy keto big mac casserole takes the traditional Big Mac flavors (hamburger, cheese, pickles, Thousand Island dressing) and combines them in a healthy keto casserole. I also added a zucchini layer at the bottom, for extra veggies. GET IT NOW

Is big mac casserole keto?

Not all big mac casseroles are low carb, since some incorporate potatoes or bread dough. Always check ingredients to know if your casserole recipe will fit keto macros. However, this cheeseburger casserole recipe is keto friendly! Each serving has 3.8 grams net carbs. You can find the full nutrition info below on the recipe card.

Keto Big Mac Casserole Ingredients

This section explains how to choose the best ingredients for keto friendly big mac casserole, what each one does in the recipe, and substitution options. For measurements, see the recipe card below.

For the zucchini layer:

Zucchini – My version of this casserole has zucchini on the bottom, because I didn’t want it to be all meat. You can also swap in other keto vegetables, such as cauliflower, broccoli, or peppers. Just cook them before adding to the casserole. Olive Oil – For roasting the zucchini. You can also use avocado oil instead. Sea Salt

For the meat layer:

Olive Oil – Or avocado oil.Ground Beef – I prefer grass fed beef for the best flavor and nutrition, but any ground beef will work. I use 85/15 moderately lean ground beef and let it cook until the extra moisture evaporates, but if you use a higher fat content, you may want to drain off some of the excess grease. Ground chicken or ground turkey would also work fine.Sea Salt & Black PepperOnion – White onions are the classic option, but yellow or red is also fine.

For the assembly layer:

Thousand island dressing – You can buy it pre-made, but they usually have added sugar, so I recommend making your own keto thousand island dressing in a medium bowl before you begin. This is our ‘big mac sauce’!Shredded cheese – I used cheddar, but you can use any keto cheese you like.

Big mac keto casserole toppings:

Iceberg lettuce – I prefer to cut my own, but you can also find shredded iceberg lettuce in the bagged lettuce section of the grocery store. Tomato – I prefer roma tomatoes, but any tomato will work. Pickles – Sliced into circles. Make sure to choose dill pickles that are made without sugar… or make homemade pickles!Thousand island dressing – More of the same kind you used above.Sesame seeds

How To Make Big Mac Casserole

This section shows how to make low carb big mac casserole with step-by-step photos and details about the technique, to help you visualize it. For full instructions, including amounts and temperatures, see the recipe card below.

Roast zucchini. Arrange zucchini slices in a single layer on a baking sheet. Brush with oil, and season with sea salt. Roast until tender.

TIP: After roasting, gently pat zucchini dry with paper towels to soak up any extra water or oil. This will prevent a watery casserole.

Brown ground beef. Heat oil in a saute pan or large skillet, and add ground beef. Season with sea salt and black pepper. Cook until the beef browns and any extra moisture evaporates.Add onion. Stir in diced onion and cook until translucent or starting to brown (up to you!).

Assemble. Arrange zucchini slices at the bottom of a casserole dish, overlapping slightly. Top with dressing, ground beef mixture, and shredded cheese.Bake. It’s done when the casserole is warm and the cheese is melted.Top. Add fresh toppings and drizzle with dressing. Sprinkle with sesame seeds.

Storage Instructions

Store the casserole (preferably with the toppings separate!) in the refrigerator for 3-4 days.

Can you freeze big mac casserole?

Yes, you can freeze the casserole, but don’t add the toppings. Store in an airtight container in the freezer for 2-3 months. Add fresh toppings once you’ve reheated it.

Reheating instructions:

Reheat the casserole (without toppings) in a 350 degree F oven or in the microwave. Once it’s hot, add toppings.

More Easy Low Carb Casserole Recipes

If you like this big mac casserole keto recipe, you might also like some of these other low carb casserole recipes:

Reuben Casserole Eggs Benedict CasseroleMexican CasseroleLoaded Cauliflower Casserole

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