You'll love this Italian Sausage and Egg Casserole featuring bell peppers, red onion, Fontina and Parmesan! It's low-carb, gluten-free and keto-friendly. It's the perfect breakfast for a crowd, make-ahead brunch recipe or breakfast-for-dinner idea!

I had to do it. I had to take one of our favorite dinners and turn it into an Italian sausage breakfast casserole featuring eggs, peppers, onions, Fontina and Parmesan.
Oh, yes, my friends.
If you love my Baked Sausage, Peppers and Onions and my Italian Sausage Sandwiches, you must try this breakfast bake! And guess what? It's a sausage and egg casserole without bread, so it happens to be low-carb, keto-friendly and gluten-free!
We all love it. Whenever I make it, my hubby may or may not hover near the oven asking "Is it ready yet?"
Recipe ingredients
Italian Sausage: Buy ground sausage in a package or ask the butcher to grind it for you. Otherwise, you’ll have to take the casing off of sausage links and break up the meat.
I always use sweet Italian sausage and recommend it for serving to guests. You can use hot Italian sausage, but keep in mind, not everyone can handle spicy-hot dishes.
You might want to buy extra to make this Italian Sausage Bread or Orecchiette with Rapini and Sausage!
Bell Peppers: I love the sweetness of orange, yellow, or red bell peppers, but you can use green ones if you prefer. You just need two.
Onions: Red onions taste delicious here, with a hint of sweetness. But feel free to substitute Vidalia onions (also sweet) or white onions, which are milder.
Fontina: Fontina is a rich and creamy, semisoft cheese with a mild, buttery, nutty flavor. I love it and also use it in my Broccoli au Gratin.
But you can use Swiss cheese instead.
Parmesan Cheese: I prefer freshly grated Parmesan for better texture and flavor, but you can use canned Parmesan if that's what you have.
Milk: Use whole milk or 2% milk. If you want, you can use half and half for extra richness.
How to make a sausage and egg casserole
See the card at the end of this post for the full recipe, but here's an overview.
Prep the sausage, peppers and eggs
- Brown the sausage crumbles in a 12-inch skillet (affiliate link).
- Sauté the chopped peppers and onions.
- Drain the vegetables in a colander (affiliate link) and pat them dry with paper towels.
- Beat the eggs and whisk them with milk.
Assemble the breakfast casserole
- Place the cooked sausage in the bottom of a greased 9x13 pan (affiliate link).
- Stir in the drained peppers and onions.
- Add the grated Parmesan and Fontina cheeses.
- Pour the egg mixture over the top.
Bake the sausage and peppers casserole, uncovered, until it's set and lightly browned on top.
Recipe tips
- Drain the cooked peppers and onions well and pat them dry so the casserole isn’t soggy.
- Feel free to use leftover sausage, peppers, and onions that you cooked for dinner! Just remove the casing from the meat and chop everything up, pat it dry and add it cold to the casserole pan.
- Store leftovers covered with foil instead of plastic wrap so there isn’t extra moisture.
What to serve with it
This Italian sausage egg bake makes an excellent brunch dish or breakfast-for-dinner recipe. For breakfast or brunch, serve it with roasted potatoes with Italian seasoning and Italian strawberries.
For dinner, it's perfect with The Best Italian Green Salad and a side of Homemade Italian Bread, if carbs aren't an issue.
Frequently asked questions
Sure! Just halve the ingredients and bake as directed.
You can assemble this low-carb breakfast casserole up to 24 hours in advance before baking it. Store the unbaked casserole covered in the refrigerator, then bake as directed.
I haven't tried freezing this sausage and egg bake. I suspect it would turn out soggy when thawed, since there is no bread in it to absorb the liquid.
More recipes like this
- Italian Peppers in Oil
- Asparagus Frittata
- Baked Arugula Frittata
- Basted Eggs
- Italian Zucchini Bake
- Pasta Frittata
Enjoy!
If you try this Italian Sausage and Egg Casserole recipe, please leave a comment and a rating!
Italian Sausage and Egg Casserole
Ingredients
- 2 medium red, yellow or orange bell peppers
- 1 cup chopped red onion
- 8 ounces Fontina cheese
- 1 cup + 2 tablespoons grated Parmesan cheese (divided use)
- 1 pound ground sweet Italian sausage (see notes)
- 1 tablespoon olive oil
- 1/16 teaspoon salt
- 1/16 teaspoon pepper
- 1/16 teaspoon garlic powder
- 8 extra-large eggs
- 1 ½ cups milk (2% is fine.)
Instructions
- Lightly grease a 9x13 pan with cooking spray. Preheat your oven to 375 degrees F.
- Rinse and dry the peppers and cut the stems out. Cut each pepper in half, then in half again. Remove the seeds and membranes. Then slice the peppers and chop them into pieces about ½ inch long. Set them aside.
- Peel and chop the onion (start with 1 medium one) and measure out 1 cup of chopped onion.
- Shred the Fontina on a box grater (or you can partially freeze the cheese and then throw it in your blender to grate it).
- Place the crumbled sausage in a 12-inch skillet and break it up with a wooden or plastic spoon. (If you are starting with sausage links instead of crumbled sausage, cut the links in half and use a small, sharp knife to remove the casings. It will be easier to break the meat up with your hands than trying to do it with a spoon.)
- Turn the heat on medium high to brown the sausage. Stir the sausage often until it is no longer pink. Using a slotted spoon, transfer the cooked sausage to your baking pan.
- In the same skillet, and keeping the small amount of sausage fat that there, add a tablespoon of olive oil and heat it on medium high. Add the onions and peppers and give them a stir. Lightly sprinkle on the salt, moving from the top to the bottom of the pan in rows. Sprinkle on the black pepper and garlic powder, again covering all of the veggies.
- Sauté the peppers and onions, stirring often, for 5-6 minutes, or until they are tender. Transfer the veggies to a colander in the sink to drain. Use paper towels to carefully pat them and absorb excess liquid. Then transfer the drained peppers and onions to your baking pan and stir them into the sausage.
- Stir the Fontina and 1 cup of Parmesan into the sausage and peppers.
- In a medium bowl, whisk the eggs well. Then, whisk in the milk. Pour the egg mixture over the sausage and peppers. Sprinkle on 2 tablespoons of Parmesan. Bake, uncovered for 40 minutes, or until the top is set and browned a bit, and a cake tester or toothpick inserted in the center comes out clean.
- Let the casserole rest for five minutes before cutting into it and serving. Store leftovers in the fridge, covered with foil (not plastic, because that will create too much moisture). Use within four days.
Notes
- If you don't see ground Italian sausage in the meat department, try asking your grocer's butcher for it. Otherwise, you'll have to buy the links and remove the casing to crumble the meat.
- You can assemble this up to 24 hours in advance before baking it. Store the unbaked breakfast casserole covered in the refrigerator, then bake as directed.
- This recipe can be halved for an 8x8 pan.
Nutrition
(Recipe Source: Cooking with Mamma C. Originally published on June 1, 2016 and updated now with new photos and additional information. Photos by Kanyi Muraguri for Cooking with Mamma C. )
Brenda Mitchell says
You have the absolutely best recipes. My family loves them. So do I. Thank you for sharing ❤️
Mamma C says
Hi Brenda - I'm so happy to hear that! Thank you for letting me know.