This Butternut Squash Breakfast Casserole made with eggs, lean turkey sausage, butternut squash, spinach, and red onion is a filling and nutritious breakfast that is great for meal prep. Easy to make and full of flavor.
This hearty butternut squash and egg breakfast casserole will feed a crowd! It's made with all whole ingredients including butternut squash, turkey sausage, and fresh spinach for a hearty breakfast that is as nutritious as it is delicious.
Sausage and butternut squash has been one of my favorite combinations for a long time. Usually, when I pair the two, it is in a simple hash. But lately, I have been making lots of egg casseroles for breakfast during the week, and my beloved squash and sausage are the perfect combination.
Not only is it packed with protein, but it's also extremely filling. It will keep you going all morning. I like to add spinach to mine for some greens as well as red onion. You could also add bell peppers, mushrooms, and no one would blame you if you threw some cheese on top.
Key Ingredients For Butternut Squash Breakfast Casserole
This casserole is packed with heart-healthy and fiber-rich whole ingredients. I don't usually like to follow diet trends, but it does qualify as Whole30 compliant. That means that all the ingredients are whole foods without any added sugars of any sort (and no dairy either).
Here's a little bit more information about the ingredients I used:
- Turkey Sausage: I used lean ground turkey sausage because it's a leaner meat than pork. If you want to use pork sausage, I suggest staying away from any that has added syrups or sugar in it.
- Olive Oil: You can substitute olive oil with avocado oil or even coconut oil. Some people that are following a dairy-free diet might want to use ghee.
- Onion: I think that red onion has the best flavor in this casserole. You could also use white or yellow onion instead.
- Salt And Pepper: Only use as much as you need to give it a little extra taste.
- Spices: For the dried herbs, I used garlic powder and oregano, but you could also sprinkle in some parsley. I love how it brings out the sweeter notes in the butternut squash.
- Butternut Squash: Peel and dice it. You might even be able to find peeled and diced butternut squash in the frozen food section.
- Eggs: You will need both the eggs and the egg whites.
Note: For a full list of ingredients and detailed instructions on how to make this breakfast casserole, take a look at the printable recipe card at the bottom of this post!
What To Serve With Sausage Squash Casserole
This is a very hearty casserole that tastes amazing all by itself. It has vegetables, eggs, and sausage - it's an entire meal.
On the side, you could serve some applesauce oatmeal muffins for some gut-healthy fiber. If you have a sweet tooth, then make some blueberry oatmeal muffins instead. Both choices are incredibly popular with groups and take almost no time to make.
Recipe Tips And Ideas For Squash And Sausage Casserole
Follow these tips to make sure the casserole comes out perfectly every single time.
- Always preheat your oven while you prep the rest of the ingredients. Your casserole will bake so much better if you put it into a preheated oven.
- Chop the butternut squash up evenly. To save yourself time, you can also choose to use frozen diced butternut squash. If you use frozen, let it thaw and then pat it dry so it doesn't turn mushy in the bake.
- If your oil is spitting at you while you saute the squash and onion, turn the heat down. You can also add a bit of water if you notice things start to burn.
- Spray your cooking dish with cooking spray before you add the casserole ingredients to it. This recipe tends to stick to most dishes.
- You could also turn this recipe into breakfast muffins. Just pour the ingredients into a prepared muffin tin and bake for 30 minutes - or until a toothpick comes out clean.
Frequently Asked Questions
Here are some questions I frequently get asked about by some readers...
Can I use a different type of squash instead of butternut?
No, I do not suggest you try to use any other type of squash. Even though I am usually supportive of swapping ingredients, there really aren't any other types of squash with the same shape or texture as butternut. The only one that comes close is acorn squash.
You can use sweet potatoes in place of butternut squash - they take the same length of time to cook and have a very similar taste and texture.
When is butternut squash in season?
Butternut squash is available year-round. If you want to get it from your local farmer's market, you will have the most luck finding it early fall until the start of winter.
How can I sweeten butternut squash breakfast casserole?
If you want it to taste sweet, add a small bit (about a teaspoon) of honey to it before you bake it.
How do you store leftover casserole?
Store leftovers in an airtight container in the refrigerator. It will stay fresh for up to 5 days.
More Breakfast Recipes You'll Love:
Butternut Squash Breakfast Casserole With Sausage
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- 1 lb. lean ground turkey sausage
- 2 tsp. olive oil
- 2 cups butternut squash, peeled and diced
- 1/2 red onion, diced
- 1/2 tsp. salt
- 1/2 tsp. garlic powder
- 1/2 tsp. oregano
- 1/2 tsp. pepper
- 4 cups spinach, chopped
- 4 eggs
- 4 egg whites
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- Nutritional Information
Add the olive oil to the pan. Once hot, add the butternut squash and red onion. Cook for 8-10 minutes until squash and onion are tender, adding 1-2 tablespoons of water if burning. Add the salt, garlic powder, oregano, and pepper. Stir together. Add the spinach and cook until it wilts, about 1-2 minutes.
* Percent Daily Values are based on a 2,000 calorie diet. Your daily values may be higher or lower depending on your calorie needs.
The Nutritional Values provided are estimates only and may vary based on the preparation method.
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