Keto Cheeseburger Casserole

Ingredients

You'll only need a few simple ingredients to make this recipe. The exact measurements are included in the recipe card below. Here's an overview of what you'll need:

Olive oil: My favorite oil to cook with! It's so flavorful. Other options include avocado oil and ghee.
Extra-lean ground beef: I prefer to use extra-lean ground beef (93% lean) because I drain the rendered fat anyway. However, using lean ground beef (85% lean) is OK if that's what you have. As you can see in the photo below, I sometimes use it.
Onion and garlic. Sometimes, when I'm lazy, I sub onion and garlic powders... but it's not the same.
Kosher salt and black pepper: If using fine salt instead of kosher salt, reduce the amount you use by half.
Mayonnaise: I prefer mayonnaise made with avocado oil.
Ketchup: I prefer unsweetened ketchup.
Mustard: I usually like Dijon mustard. But in this recipe, yellow mustard works too.
Shredded cheddar: I like to use sharp or extra-sharp cheddar. It greatly enhances the flavor of this casserole.

The ingredients needed to make a keto cheeseburger casserole.

Variations

The best thing about this recipe is how simple it is to make. But if you'd like to experiment a little, here are a few ideas for you:

Add crumbled cooked bacon. I love the flavor it adds.
You can make this recipe with ground chicken or turkey thighs. It won't be the same, but it's still good. I recommend using ground thighs and not ground breast, which is too lean.
Add your favorite spices, even if they're not classic cheeseburger seasonings. Smoked paprika and chili powder are excellent in this recipe.
Sometimes I mix sliced pickled jalapenos into the beef mixture before baking it.

Cheeseburger Casserole Instructions

The detailed instructions for making this recipe are included in the recipe card below. Here's an overview of the steps:

You start by cooking ground beef and onion in olive oil. (Photo 1).
Add seasonings: Garlic, salt, and black pepper. (Photo 2).
Off heat, you stir in condiments: Mayo, ketchup, and mustard. (Photo 3).
Stir in shredded cheese. (Photo 4).
The last step is to transfer the mixture to a greased baking dish and sprinkle it with more cheese. Bake the casserole for about 15 minutes at 400°F, then serve! (Photos 5,6).

A six-photo collage showing the steps for making a low-carb cheeseburger casserole.

Recipe FAQs

What type of beef do you use?

I use extra lean ground beef (93% lean). I use lean ground beef (85% lean) in most of my recipes, but when I cook it for a casserole, I drain the fat anyway.

Can I add vegetables?

Absolutely! One option mentioned above is to add riced cauliflower
to the beef/onion mixture.

You can also add two cups (about 2 ounces) of raw baby spinach leaves to the beef mixture when it's done cooking. Add the spinach right before adding the seasonings and mix it in until it wilts very slightly. Don't overcook it.

Can you make a casserole without a starchy ingredient?

Yes! A classic casserole contains protein (meat, poultry), starch (rice, potatoes), vegetables, sauce, and cheese.

But one of the best things about casseroles is that they are flexible and forgiving, so you can adapt them to your needs and the ingredients you have on hand. Made as written, this casserole contains just protein, sauce, and cheese and is delicious.

Storing Leftovers

You can keep the leftovers in the fridge, in an airtight container, for 3-4 days. Reheat them gently, in the microwave, at 50% power. You can also freeze individual servings for up to three months.