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This Whole30 breakfast casserole with sausage, eggs, spinach, and mushrooms is flavorful enough to live off of during a Whole30. You’ll love this healthy, paleo breakfast casserole because it’s packed with flavor, protein, and fiber, making you feel a-freaking-mazing all day. 

Whole30 breakfast casserole with sausage, spinach, and mushrooms in a baking dish

Any time we’re on a Whole30, I spend a couple hours on Sunday afternoon, making dishes for the week. This usually looks like a batch of Whole30 garlic mayonnaise, Whole30 chicken salad, and Whole30 ranch dressing. But one Sunday, I was struck by the strangest, strongest urge to make a sausage and veggie bake, filled with chopped spinach, fresh tomatoes, sautéed mushrooms, homemade spicy breakfast sausage, and fresh herbs.

And you know what? I never tired of eating this Whole30 and paleo breakfast casserole that week, not once! No, I fell in love with the creamy egg bake, the rich sausage, the fresh veggies, the flavorful herbs. This is saying a lot, considering I need a savory breakfast to be absolutely top notch to maintain my attention.

Eggs pouring over Whole30 breakfast casserole with sausage, mushrooms, eggs

Even better, I felt amazing after eating it, which is one of my very favorite things about eating a Whole30 breakfast. There’s no heaviness or energy slump. Nah, you feel light and energized and full until lunch. With loads of veggies and plenty of protein, this Whole30 breakfast casserole with sausage, eggs, spinach, and mushrooms might just be Whole30-perfect.

Why this Whole30 breakfast casserole is so good:

  • It’s the Whole30 breakfast casserole for Whole30 breakfast casserole haters. It’s packed absolutely full of flavor and contains tons of protein.
  • It isn’t heavy, and there’s great fiber content, too. This dish is one where I combined basically everything good I could think of and included all my favorite veggies: sausage, mushrooms, tomatoes. We had fresh basil on hand, so of course I added it. However, you’d be fine without it, or you could substitute dried basil easily.
  • This Whole30 breakfast casserole comes together quite easily, making your Sunday meal prep easier than ever.
Slice of Whole30 breakfast casserole with sausage on a plate with casserole in background

On top of being oh-so-flavorful, it’s super easy and pretty darn quick… major bonus points for anything Whole30, if you know what I mean. The directions go basically as follows: sauté stuff, pour eggs over, bake, um… eat? As much as I freaking love making mayonnaise all the time (liar, liar, pants on fire), I am all about some efficiencies in the kitchen.

Veggies and sausage for Whole30 breakfast casserole


  • This Whole30 breakfast casserole is super versatile, so you can try it with different meats (Bacon is great!) or veggies. Sun-dried tomatoes would be awesome in this.
  • Increase the eggs to 12 for an eggier paleo breakfast casserole that makes a bit more.
  • Swap out roasted sweet potatoes for the mushrooms if you’re not a fan of fungi.
  • Evenly distribute the veggie filling among the cups in a muffin tin and pour the eggs over for an on-the-go breakfast option.


  • Don’t overbake this Whole30 breakfast casserole! Cook it until it’s just set and a knife inserted into the center comes out clean.
  • Make sure you squeeze the water out of your thawed spinach, otherwise you’ll end up with a watery mess! If you do forget, just sauté the veggie mixture longer or until the water is evaporated.
Veggies and sausage for Whole30 breakfast casserole

Recipes You’ll Also Love

Recipe By: Cheryl Malik
4.96 from 68 votes

Whole30 Breakfast Casserole with Sausage, Eggs, Spinach, and Mushrooms

Prep 15 minutes
Cook 35 minutes
Total 50 minutes
This Whole30 breakfast casserole with sausage, eggs, spinach, and mushrooms is flavorful enough to live off of during a Whole30. You’ll love this healthy, paleo breakfast because it’s packed with flavor, protein, and fiber.
9 servings


  • Large bowl
  • Medium skillet
  • 9×13 baking dish
  • Medium bowl


  • 1 pound Whole30-compliant breakfast sausage see below for recipe
  • 3 cups button mushrooms sliced
  • olive oil as needed
  • 6 green onions sliced
  • 3 Roma tomatoes seeded and diced
  • 1 tablespoon fresh basil chopped, or 2 teaspoons dried basil
  • 16 ounces frozen chopped spinach thawed
  • 1 ½ teaspoons salt
  • 10 large eggs

For Homemade Whole30-Compliant Breakfast Sausage

  • 1 pound ground pork
  • 1 teaspoon dried sage
  • 1 teaspoon salt
  • ½ teaspoon ground black pepper
  • 1 pinch dried marjoram
  • 1 pinch crushed red pepper flakes
  • 1 pinch ground cloves


For the Whole30-Compliant Breakfast Sausage

  • Combine all ingredients in a medium bowl and mix well with your hands. Use in recipe right away or keep in an airtight container for 1 day in the fridge.

For the Whole30 Breakfast Bake

  • Preheat oven to 350º Fahrenheit.
  • In a medium skillet over medium heat, brown and crumble sausage. Add olive oil if necessary.
  • Add mushrooms and cook about 5 minutes or until soft, stirring occasionally. Add remaining vegetables, herbs, and salt and cook about 2 minutes or until slightly softened and well combined. Pour mixture into baking dish.
  • Crack eggs into a medium bowl and whisk well. Pour over sausage-vegetable mixture and bake 25-30 minutes or until a knife, inserted in the center, comes out clean. Serve warm.


Approximate Information for One Serving

Serving Size: 1servingCalories: 268calProtein: 19gFat: 20gSaturated Fat: 6gTrans Fat: 1gCholesterol: 243mgSodium: 795mgPotassium: 573mgTotal Carbs: 5gFiber: 2gSugar: 2gNet Carbs: 3gVitamin A: 6491IUVitamin C: 8mgCalcium: 116mgIron: 3mg
Nutrition Disclaimers
Number of total servings shown is approximate. Actual number of servings will depend on your preferred portion sizes.
Nutritional values shown are general guidelines and reflect information for 1 serving using the ingredients listed, not including any optional ingredients. Actual macros may vary slightly depending on specific brands and types of ingredients used.
To determine the weight of one serving, prepare the recipe as instructed. Weigh the finished recipe, then divide the weight of the finished recipe (not including the weight of the container the food is in) by the desired number of servings. Result will be the weight of one serving.

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  1. I like this casserole but found I should of reduced or eliminated the salt b/c of the breakfast sausage is all ready salty. I also only used 8 eggs to make a smaller dish for 2-3 people in a oblong pan.4 stars

    1. Thanks so much for sharing your feedback with us, Dana! I hope you’ll give it another try with less salt and let us know if you liked it better!

  2. I made this casserole three weeks ago and ate it for four straight mornings in a row it was amazing my husband also absolutely loved it5 stars

    1. Thanks so wonderful to hear, Dyana! Love that you were able to enjoy it so many mornings in a row. Thank you so much for your review!

  3. So delicious and easy. Great base recipe where you can sub whatever veggies you have on hand. I used green onions, mushrooms, fresh spinach, shedded carrot and tomato. And Jones chicken sausage from Costco. Just cooked then sliced. Yum!5 stars

    1. So happy you enjoyed it, Ashley! We love those chicken sausages – what a great idea to use them here!

  4. I have not made this recipe yet. But it sounds delicious. I am going to attempt to Saturday. My husband only eats egg whites because of his cholesterol. Is there some kind of lower egg yoke alternative I could use to lower the cholesterol content? Thank you…5 stars

    1. Hi, Nancy! Great question. You can make this casserole using egg whites only instead of whole eggs, or half egg whites only and half whole eggs if he can have some yolks. Just be sure to use the equivalent of 10 whole eggs!

  5. This is a wonderful recipe! Instead of tomatoes, I added chopped broccoli, red bell pepper, and yellow onion. I also used roughly chopped fresh spinach instead of frozen. The meat-veggie mix made enough for 24 muffins. I baked them in two tins at 350 for 20 minutes. They turned out beautifully! Thank you for helping me to carry my Whole30 breakfasts5 stars

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