Healthy Breakfast Casserole

breakfast casserole sliced and served with spatula.

Healthy Breakfast Casserole

Course: Breakfast

Cuisine: American

Keyword: healthy breakfast casserole

Prep Time: 1

Cook Time: 45

Total Time: 1 45

Servings:

Calories: 248kcal

Author: Megan Gilmore

This healthy breakfast casserole is loaded with protein and veggies, with a sneaky vegetable hiding inside. It reminds me of Quiche Lorraine without a crust!

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Ingredients

1 (3-pound) spaghetti squash
12 ounces thick-cut bacon
1 tablespoon olive oil
1 medium yellow onion , chopped
8 whole eggs
5 ounces Gruyere cheese , shredded and divided
1 ½ teaspoons fine sea salt
1/2 teaspoon black pepper

Instructions

Preheat your oven to 400ºF and line two large rimmed baking sheets with parchment paper. Cut the spaghetti squash in half crosswise (so you only cut through the hollow middle-- easier!) and scoop out the seeds with a spoon. Place the squash cut-side-down on the pan, and bake until tender, about 45 to 60 minutes.
To cook the bacon, arrange the strips in a single layer, without overlap, on the other lined baking sheet. (Make sure it has a rim, to catch the grease as it cooks.) Place it in the same oven as the squash and let it cook until crisp, about 25 to 30 minutes, depending on the thickness. It will crisp up even more as it cools.
Once everything is in the oven, add the olive oil to a large skillet over medium heat and sauté the onion until it is soft and translucent, about 5 to 8 minutes. Set it aside to cool while everything else finishes cooking.
Let the spaghetti squash and bacon cool, until they are comfortable enough to handle. (You don't want to mix the eggs into piping hot squash, or they will scramble as you stir. This is why I recommend cooking the squash and bacon the night before you want to assemble this casserole, so you don't have as much prep time in a single day.) Once you can handle the squash, use a fork to scrape the spaghetti squash strands into a large mixing bowl. Crumble the bacon in to pieces, and sprinkle them into the bowl, too. (Reserve a few bacon pieces to sprinkle on top, if you like.)
Crack the eggs into a separate bowl (just in case you need to fish out broken egg shells later) and season with the salt and pepper. Whisk well with a fork, then pour it into the mixing bowl, along with the onions, and half of the grated cheese. Stir well.
Grease a 9" by 13" baking dish with spray oil, then pour the mixture into the pan. Sprinkle the remaining cheese over the top, along with any reserved bacon pieces. Bake until the top is golden and has puffed up, about 40 to 45 minutes at 400ºF.
When the breakfast casserole is done cooking, remove it from the oven and let it cool for 10 to 15 minutes. Slice it into 12 squares and serve warm, with a few freshly chopped chives on top, if desired. Leftovers can be stored in an airtight container in the fridge for up to 5 days.

Notes

Nutrition information is for 1 of 12 slices. This information is automatically calculated, and is just an estimate, not a guarantee.
This recipe was updated in December 2022, to increase the salt from 1 teaspoon to 1 1/2 teaspoons. If you prefer using less salt, feel free to use the original 1 teaspoon, but I think the flavor is better with the extra 1/2 teaspoon addition.
For make-ahead tips, be sure to read the full post above!

Nutrition