If you’re looking for a healthy, make-ahead breakfast option, this Whole30-compatible and low carb Mexican breakfast casserole will hit the spot! Each slice is packed with eggs, savory chorizo, zesty salsa, sweet peppers, and shredded sweet potato, so it’s the perfect on-the-go paleo meal.

My day always starts off better when I nourish myself with something jam-packed with protein and veggies—I just don’t always have the time to whip up a dish that fits the bill. That’s why I’m head-over-heels for this Mexican-inspired breakfast casserole: I can make it ahead of time and grab a slice on busy mornings. Better yet, it tastes great at any time of day so you can snarf down this meal whenever the munchies hit!

Ingredient Substitutions

The best thing about this Mexican breakfast casserole recipe is that it’s pretty flexible—you can switch out many of the ingredients and still come out with something delicious! Eggs, though, are still a must, so if you have an egg allergy, you should probably skip this recipe altogether because the eggs hold everything together.

Other than the eggs, here are some easy substitutions you can make in this recipe:

Mexican chorizo: If you don’t have chorizo, you can substitute 1 pound of ground meat seasoned with your favorite taco seasoning!
Bell peppers and poblano peppers: You can use any diced peppers in place of the bell and poblano peppers called for in this recipe—sometimes, I like to throw in a couple of Serrano peppers to boost the heat. If you don’t like peppers, diced mushrooms also work (but make sure to cook off all the liquid before adding the other ingredients).
Shredded sweet potato: I like using white sweet potatoes (e.g., Hannah variety) in this casserole, but orange-fleshed sweet potatoes also work. If you want to make a keto-friendly casserole, substitute 3 cups of riced cauliflower instead.
Roasted Tomatillo Salsa: You can use any salsa in this casserole and it’ll taste great—just use your favorite. No salsa? Diced fire roasted canned tomatoes + some chili powder also works!
Nutritional yeast: I add nutritional yeast to lend a cheese-y flavor to this dairy-free casserole, but you can leave it out if you don’t have it.

How do you make this ahead?

This casserole can be made ahead and stored in a sealed container in the refrigerator for up to four days. You can also wrap up the individual slices and freeze them for up to 4 months. (If you freeze them, you can thaw the slices in the fridge overnight.)

To heat the slices up, just nuke it ’em the microwave for about a minute or until heated through. Alternatively, pop it in a toaster oven at 325°F for about 6 to 8 minutes or until piping hot. Truth be told, the slices taste great cold right out of the fridge, too!

What do you serve it with?

I love eating a slice of this Mexican Breakfast Casserole all by itself, but you can adorn it with your favorite taco toppings like sliced avocado, sliced scallions, dairy-free sour cream, guacamole, or more salsa! It also tastes great with a side salad or my Mexican Cauliflower Rice!

Let’s make Mexican Breakfast Casserole!

Serves 8

Ingredients

1 tablespoon avocado oil
1 small onion, diced
1 red bell pepper, diced
1 poblano pepper, diced
1½ teaspoons Diamond Crystal kosher salt, divided
3 garlic cloves, minced
1 pound Mexican chorizo
3 cups shredded white sweet potatoes (e.g., Hannah variety)
1½ cups roasted tomatillo salsa
12 large eggs
¼ cup coconut milk, almond milk, cashew milk, or favorite non-dairy milk
¼ cup nutritional yeast
1 teaspoon dried oregano
¼ teaspoon freshly ground black pepper
2 avocados, peeled and thinly sliced (optional topping)
2 scallions, thinly sliced (optional topping)

Equipment

All my favorite kitchen tools are listed here.

Method

Heat oven to 400°F with the rack in the middle. While the oven is warming up, heat a large 12-inch skillet over medium heat. Swirl in the avocado oil when the pan is hot.

Add the onion, bell pepper, and poblano pepper.

Sprinkle ½ teaspoon kosher salt on the vegetables and cook for about 5 minutes, stirring frequently until slightly softened.

Throw in the minced garlic and sauté until fragrant, about 30 seconds.

Dump in the chorizo and use a spatula to break it up.

Cook, stirring frequently, until the chorizo is nicely browned, about 5 minutes.

Take the pan off the heat and mix in the grated sweet potatoes and salsa.

Stir to combine and set aside to cool slightly.

In a large bowl, whisk together the eggs, milk, nutritional yeast, oregano, 1 teaspoon kosher salt, and ¼ teaspoon black pepper.

Grease a 9-inch x 13-inch casserole pan with avocado oil spray.

Transfer the cooked chorizo and vegetables to the pan and spread the contents evenly.

Pour the egg mixture on top.

Pop it in the oven and bake for 30 to 40 minutes, rotating the tray at the halfway point.

The casserole is finished when the top is golden and a toothpick comes out clean when inserted in the middle.

Take the casserole out and leave it to cool for 5 to 10 minutes. Then, slice it up…

…and top with sliced avocado and scallions if desired!

Want to make a Tex-Mex inspired casserole? Try my Tex-Mex Beef and Rice Casserole!

Looking for more recipe ideas? Head on over to my Recipe Index. You’ll also find exclusive recipes on my iPhone and iPad app, and in my cookbooks, Nom Nom Paleo: Food for Humans (Andrews McMeel Publishing 2013), Ready or Not! (Andrews McMeel Publishing 2017), and Nom Nom Paleo: Let’s Go! (Andrews McMeel Publishing 2021).

Mexican Breakfast Casserole