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I have been making some variation of this breakfast casserole since this past Christmas morning, when I made Andrew Feinberg’s broccoli frittata, which was very well received (by the four adults sitting at the table).
What differentiates Andrew’s frittata from others is the cooking method, and in particular, the unusually low oven temperature — 250ºF — which prevents the custard from becoming dry and granular.
Like many frittata recipes, Andrew’s starts on the stovetop and finishes in the oven. In the recipe included below, the eggs cook entirely in the oven, moving it out of the frittata territory, making it more of an egg bake or a casserole (though there’s no cream or milk).
This recipe should be used as a guide and tailored to your tastes and preferences. I like a little bit of greens, a little bit of cheese, a little bit of onion, and a little bit of sausage, which makes the casserole feel a bit more substantial and precludes the need for cooking other breakfast meat on the side, which is especially nice when entertaining.
Here’s a rough framework:
The Makings of A Very Nice Breakfast Casserole
- Eggs: Estimate about 2 per person.
- Salt: A good rule of thumb: 1/2 teaspoon kosher salt for every 4 eggs.
- Something green. I like spinach, because it’s so low maintenance. No need to cook it — simply toss it with the hot sausage and onions, the heat of which will gently wilt it. Other options: roasted asparagus or broccoli, finely chopped Swiss chard or kale, etc.
- Cheese: I like Gruyère or Fontina. For 12 eggs, 4 ounces of grated cheese is about right.
- Onions: If you have the time to caramelize or near-caramelize an onion, do it. Otherwise, chopped scallions or chives will add that nice allium flavor, while also providing more green color.
- Sausage: I love hot Italian sausage here. The spices in the sausage flavor the custard, and the subtle spiciness is nice. Also: spinach + sausage is always a good match.
Breakfast casseroles or egg bakes are great for — wait for it — breakfast or brunch, especially when entertaining. But they also make great, low-key dinners, and the format can be used to clean out the odds and ends in your vegetable bins. Cold or re-heated, the leftover casserole makes a fine lunch on subsequent days, too.
This is how I like to make this breakfast casserole: Start by browning the sausage.
Pour it over a heap of spinach in a colander — this serves to both gently wilt the spinach and drain off excess fat and moisture.
Caramelize or nearly caramelize an onion, if you wish.
Transfer the onion to the colander as well.
Toss to combine and further wilt the spinach.
Transfer to a 9×13-inch pan and cover with grated cheese. (Love this 9×13-inch USA Pan.)
Beat 12 eggs.
Pour the eggs over top.
Bake until custard is just set.
Sausage, Egg, and Cheese Casserole with Spinach
- Prep Time: 20 minutes
- Cook Time: 40 minutes
- Total Time: 1 hour
- Yield: 6 to 8 servings
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Use the proportions below as a guide. You can omit the sausage to make it vegetarian. If you want to scale it up or down, a good rule of thumb is 1/2 teaspoon kosher salt for every 4 eggs.
Ingredients
- 2– to 4-oz baby spinach (I typically use 3 ounces)
- 1 tablespoon olive oil, plus more as needed
- 0.5 – 0.75 lb. hot Italian sausage
- 1 yellow onion, thinly sliced or diced
- 1.5 teaspoons kosher salt, plus more as needed
- 4 oz. grated cheese, I like Gruyère or Fontina
- 12 eggs
- freshly cracked black pepper to taste.
Instructions
- Heat oven to 250ºF. Place spinach in a large colander and set it in the sink. Grease a 9×13-inch pan lightly with butter or with nonstick spray.
- In a medium skillet over medium-high heat, heat the oil till it shimmers. Cook the sausage till it browns and is nearly cooked through, about 5 minutes. Break it up with a spoon or a spatula as it cooks. Spoon the sausage over the spinach in the colander in the sink. Return the skillet to the stove top, add a little bit more oil to the pan if necessary, and set it over medium heat. Add the onions. Season with salt. Cook the onions till they begin to caramelize, 7 to 10 minutes. Spoon the onions over the sausage and toss with a spatula or large spoon to gently wilt the spinach. Transfer the spinach-sausage mixture to the prepared pan. Spread the cheese over top.
- Break the eggs into a large bowl, season with the 1.5 teaspoons salt and fresh cracked pepper to taste. Beat with a whisk until the eggs are well blended. Pour the eggs into the pan. Season with more pepper to taste. Transfer pan to the oven and bake for 30-40 minutes, rotating the pan halfway through. Start checking at 30 minutes, then every 5 minutes thereafter till it’s done — depending on your oven and the material of the pan you are using, it may take more or less time to cook.
- Remove pan from the oven, and let it cool for 5 minutes before serving.
- Category: Breakfast
- Method: Oven
- Cuisine: American
Keywords: egg, casserole, sausage, cheese, spinach
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Rebecca says
I make a similar recipe and make a batch of focaccia in the same size pan to split for breakfast sandwiches to feed a crowd. It is economical and looks nice enough for a brunch or shower.
alexandra says
I love doing this as well! Haven’t in awhile, but I’m thinking it would be so much fun for a spring brunch.
Clare says
I had in mind to make chorizo and eggs for my Indy 500 brunch next weekend, but when I saw this recipe, I immediately saw the possibility…chorizo is sausage, right? I just finished a practice run; made 1/2 batch in an 11×7 pan. I used thinly sliced shallots (not caramelized) in place of the onion. I am very pleased with the result. Chorizo is bold like hot Italian sausage, but has a completely different personality – I think sliced avocado on the side will be complementary. Tartine blueberry scones will be good with this, too.
alexandra says
So happy to hear this, Clare! Chorizo sounds delicious as does avocado as a side … totally trying this ASAP. And yes to Tartine scones, too. Enjoy your brunch! Sounds like a blast.
Kara says
Delicious! I was skeptical about the 250 degree cooking temperature but the texture of this is superb. Will definitely make this again!
★★★★★
alexandra says
Wonderful to hear this, Kara! And I know: I was, too 🙂
Kathy says
Wondering if anyone else has ended up with runny liquid, after 40”? I made yesterday for Father’s Day. I used 10 eggs, several handfuls of spinach. I couldn’t tell if it was liquid from the spinach or if the eggs weren’t cooked—they didn’t cover the spinach as shown in picture. Maybe next time I will sauté the spinach a bit to release moisture? Was easy & tasty.
alexandra says
Hi Kathy, I have not had the runny liquid experience with this recipe — bummer! Question: did you toss the spinach with the warm onions and sausage in a colander? Sautéing is a good idea, too — you can add it to the pan with the onions. I would probably drain it as well in a colander after sautéing. Glad it was easy and tasty despite the liquid!
Susan Turnquist says
Can I make this the night before? By the way, I used to work with your father-in-law in surgery at Children’s Hospital in Saint Paul. He was one of my favorite docs to work with. He used to talk about your cooking all the time and was the one who directed me to your website. I am forever grateful for the tip. Tell him hello from Susan Turnquist, that I have retired and have 2 lovely grandkids now. Merry Christmas and thanks for all the great recipes.
alexandra says
Hi Susan! Merry Merry Christmas to you … and so sorry for the delay here. You were probably looking for an answer a few days ago. Richard is going to love hearing from you. He truly is the best. I am so lucky to have him as a father-in-law.
But yes! You can definitely make it the night before. Do you mean bake it the night before? Or just mix up the egg, sausage, spinach mixture? You can do either.