Okay, confession time: Mornings can be rough. Between trying to get everyone (including myself) out the door and figuring out what to eat, sometimes breakfast feels like an Olympic sport. That’s where this Savory Low-Carb Sausage & Mushroom Casserole became my superhero. It started as a weekend brunch experiment, but it was so ridiculously tasty and easy to reheat that it quickly became a weekday morning staple.
Forget bland egg dishes – this casserole is packed with savory Italian sausage, earthy mushrooms, and plenty of melty cheese, all baked into a satisfyingly fluffy egg base. It’s the kind of comforting, hearty food that feels like a hug, but secretly fits right into a low-carb lifestyle. Whether you need a crowd-pleasing brunch dish, a simple weeknight dinner, or something delicious to grab on busy mornings, this casserole has seriously got your back.
Why You’ll Love This Recipe
- Flavor Explosion: The combination of savory Italian sausage, umami-rich mushrooms, garlic, and cheese is just chef’s kiss. The optional pinch of red pepper flakes adds a gentle warmth that wakes everything up.
- Seriously Satisfying & Low-Carb: It’s packed with protein and healthy fats to keep you full and energized, all while keeping the carbs super low. Perfect if you’re watching your carb intake or just want a hearty meal that won’t weigh you down.
- Make-Ahead Magic: This casserole is fantastic for meal prep! Bake it once and enjoy delicious, ready-to-go breakfasts or lunches throughout the week. More on that below!
Let’s Talk Ingredients
Here’s what you’ll need to whip this up:
- 15 oz Italian Sausage: Pork or turkey both work great! Choose mild or hot depending on your preference.
- 12 oz Fresh Mushrooms: Cremini (baby bella) or white button mushrooms are perfect. Pre-sliced save time, but whole work too – just give ’em a quick slice.
- 8 large Eggs: The backbone of our casserole!
- 3/4 cup Cottage Cheese: Trust me on this! Rinsing it removes some liquid and gives the casserole a lighter, fluffier texture without a strong cottage cheese flavor. Low-fat is recommended.
- 1.5 cups shredded Mozzarella Cheese: Divided – half goes inside, half goes on top for that glorious cheesy crust. Feel free to use a mix like Mozzarella-Provolone if you like!
- 3 Tbsp grated Parmesan Cheese: Adds a salty, nutty depth.
- 3 Tbsp sliced Green Onions: For a mild oniony freshness.
- 3 tsp Olive Oil: Divided for cooking the sausage and mushrooms.
- 3/4 tsp Spike Seasoning (or your preferred all-purpose blend): Spike is great, but any savory blend you like with eggs works!
- 1/4 tsp Garlic Powder: Because garlic makes everything better.
- Pinch of Red Pepper Flakes (optional): Adds a tiny kick! Adjust to your heat preference or leave it out.
- Freshly Ground Black Pepper: To taste.
Equipment Needed:
- Large non-stick skillet
- Medium casserole dish (around 8×11 inches is ideal)
- Fine mesh strainer (for the cottage cheese trick!)
- Medium mixing bowl
Step-by-Step Guide to Casserole Heaven
- Get Ready: First things first, preheat your oven to 365°F (185°C). Give your casserole dish a quick spray with cooking spray or a light coating of olive oil.
- Brown That Sausage: Heat 1.5 tsp olive oil in your skillet over medium-high heat. If your sausage is in casings, remove them. Crumble the sausage into the hot skillet and cook, breaking it up with a spoon, until it’s nicely browned and cooked through (about 5-7 minutes). If you’re using red pepper flakes, toss them in during the last minute. Drain off any extra fat – this keeps the casserole from getting greasy. Spread the cooked sausage evenly in your prepared dish.
- Sauté the ‘Shrooms: Wipe out the skillet if needed, add the remaining 1.5 tsp olive oil, and get it hot over medium-high again. Add your sliced mushrooms. Let them cook, stirring now and then, until they release their water, it evaporates, and they start to get nicely browned (about 6-8 minutes). This browning step adds tons of flavor! Scatter the mushrooms over the sausage.
- First Cheesy Layer: Sprinkle half of your mozzarella (that’s 3/4 cup) and all the sliced green onions over the sausage and mushroom layer.
- Whip Up the Egg Mixture: While the sausage and mushrooms were cooking, you could tackle this step! Put the cottage cheese in your fine mesh strainer and give it a gentle rinse under cold water. Let it drain really well – you can even press it lightly with a spoon to squeeze out extra water. In your mixing bowl, whisk those eggs until they’re well combined. Stir in the drained cottage cheese, Parmesan, Spike seasoning (or your choice), garlic powder, and a few grinds of black pepper.
- Bring It All Together: Pour the egg mixture evenly over everything in the casserole dish. I like to use a fork to gently poke around a bit, making sure the egg mixture gets into all the nooks and crannies without completely mixing up the layers.
- Top It Off: Sprinkle the remaining 3/4 cup of mozzarella cheese evenly over the top.
- Bake Away: Pop that beauty into the preheated oven. Bake for 35-40 minutes. You’ll know it’s done when the center feels firm if you gently press it (no jiggle!) and the top is beautifully golden brown.
- Let It Rest! This is important! Let the casserole sit on a wire rack for about 5-10 minutes before you slice into it. This helps it set up properly so you get nice clean slices.
Expert Tips & Tricks
- Cheese Swaps: Feel free to swap the mozzarella for Monterey Jack, Provolone, or a Colby blend. Adding a little sharp cheddar to the mix is also delicious!
- Veggie Boost: Want more greens? Stir a cup of fresh baby spinach into the mushrooms during the last minute of cooking until it just wilts.
- Sausage Options: Can’t find Italian sausage? Regular breakfast sausage works, but you might want to add a pinch of dried oregano or fennel seed to mimic that Italian flavor.
- Avoid Watery Casserole: Make sure to drain the sausage well and cook the mushrooms until their liquid evaporates. Also, don’t skip rinsing and draining the cottage cheese!
- Don’t Overbake: Keep an eye on it towards the end of the baking time. Overbaking can make the eggs rubbery. The center should be just set.
Meal Prep Superstar Section!
This casserole is honestly amazing for meal prep. Here’s how to make it work for you:
- Bake Ahead: Bake the entire casserole as directed. Let it cool completely.
- Store Smart: You can store it covered in the fridge (either in the baking dish or sliced into portions in airtight containers) for up to 5 days.
- Reheat Gently: The microwave is your friend here! Reheat individual slices on medium power (try 50-60%) for about 45-90 seconds, depending on your microwave. Heating gently prevents the eggs from getting tough. You can also reheat slices in a toaster oven until warmed through.
- Grab & Go: Having pre-portioned slices ready makes busy mornings SO much easier. Just grab one, reheat, and you have a satisfying, protein-packed breakfast ready in minutes.
Serving & Pairing Ideas
This casserole is fantastic on its own for breakfast or brunch. For a light lunch or dinner, serve it with:
- A simple green salad with a vinaigrette dressing.
- Sliced avocado or a dollop of guacamole.
- Your favorite hot sauce for an extra kick!
- Fresh fruit on the side.
Savory Low-Carb Sausage & Mushroom Casserole
This hearty low-carb casserole features savory Italian sausage and earthy mushrooms, bound together with eggs and cheese for a satisfying meal perfect for breakfast, brunch, or meal prepping.
Equipment
- Large non-stick skillet
- Medium casserole dish (approx. 8x11 inches or similar volume)
- Fine mesh strainer
- Medium mixing bowl
Ingredients
- 15 oz Italian Sausage pork or turkey recommended
- 12 oz Fresh Mushrooms sliced (approx. 340g)
- 8 large Eggs
- 3/4 cup Cottage Cheese low-fat recommended
- 1.5 cups shredded Mozzarella Cheese approx. 6 oz / 170g, divided
- 3 Tbsp grated Parmesan Cheese
- 3 Tbsp sliced Green Onions
- 3 tsp Olive Oil divided
- 3/4 tsp Spike Seasoning or your preferred all-purpose seasoning blend
- 1/4 tsp Garlic Powder
- Pinch of Red Pepper Flakes optional, for mild heat
- Freshly Ground Black Pepper to taste
Instructions
- Prepare Oven and Dish: Set your oven to preheat at 365°F (185°C). Lightly grease your medium casserole dish with cooking spray or a little extra olive oil.
- Brown the Sausage: Add 1.5 tsp of olive oil to the large skillet over medium-high heat. Remove the sausage from its casing (if necessary) and add it to the hot skillet. Cook, breaking the sausage apart with a spoon or spatula, until it's fully cooked and lightly browned, about 5-7 minutes. Add the pinch of red pepper flakes (if using) during the last minute of cooking. Drain off any excess fat and spread the cooked sausage evenly over the bottom of the prepared casserole dish.
- Sauté the Mushrooms: If needed, wipe the skillet clean. Add the remaining 1.5 tsp of olive oil and heat over medium-high. Add the sliced mushrooms and cook, stirring occasionally, until they release their moisture and it evaporates, and the mushrooms begin to brown slightly, about 6-8 minutes. Distribute the cooked mushrooms evenly over the sausage layer in the casserole dish.
- Add First Cheese & Onion Layer: Sprinkle half of the shredded Mozzarella (3/4 cup) and all of the sliced green onions over the mushrooms and sausage.
- Prepare Egg Mixture: While the sausage and mushrooms are cooking, place the cottage cheese in the fine mesh strainer. Gently rinse it under cold water and allow it to drain very well, pressing lightly to remove excess moisture. In the medium mixing bowl, whisk the 8 large eggs until the yolks and whites are thoroughly combined. Stir in the drained cottage cheese, grated Parmesan cheese, Spike Seasoning, garlic powder, and black pepper to taste.
- Combine and Top: Pour the prepared egg mixture evenly over the ingredients in the casserole dish. Use a fork to gently poke and slightly mix the ingredients, ensuring the egg mixture coats everything without excessively disturbing the layers.
- Final Cheese Layer: Sprinkle the remaining half of the shredded Mozzarella (3/4 cup) evenly over the top.
- Bake the Casserole: Place the casserole dish in the preheated oven. Bake for 35-40 minutes, or until the center is firm to the touch (no longer jiggly) and the top is golden brown.
- Rest and Serve: Let the casserole rest for 5-10 minutes before slicing and serving. This helps it hold its shape better.
Notes
Yield: 6 Servings Serving Size: 1 slice (approx. 1/6th of casserole)
Storage and Reheating:
- Leftovers can be stored covered in the refrigerator for up to 5 days.
- Reheat individual portions gently in the microwave until warmed through (start with 45-60 seconds on medium power, checking frequently to avoid overcooking).
- Calories: 458 kcal
- Total Fat: 34 g
- Saturated Fat: 13 g
- Carbohydrates: 5.3 g
- Fiber: 0.6 g
- Sugars: 3.1 g
- Protein: 32 g
- Sodium: 755 mg
- Cholesterol: 332 mg
Give It a Try!
Seriously, this Savory Low-Carb Sausage & Mushroom Casserole has become such a staple in my kitchen, and I have a feeling it might become one in yours too. It’s easy, flavorful, and so versatile.
If you make it, I’d love to hear what you think! Happy cooking!
