Oh, you know those nights when only serious comfort food will do, but you’re trying to keep things low-carb? I totally get it! That’s exactly why I dreamed up this amazing Low Carb Philly Cheesesteak Casserole. It’s got all that amazing, gooey, savory flavor you crave from the classic, but without messing with your carb goals. I remember making this for the first time when life felt super hectic. The smell of the peppers and steak cooking just took me right back to the streets of Philly, and my family absolutely loved it! It’s become our go-to for a hearty dinner that’s both satisfying and guilt-free.
Why You’ll Love This Low Carb Philly Cheesesteak Casserole
Seriously, why is this casserole such a winner? Let me count the ways!
- Super Easy to Make: No fuss, no fancy techniques here – just simple steps for a delicious meal.
- Packed with Classic Flavor: You get all that savory steak, tender veggies, and gooey cheese goodness without the bread.
- Keto & Low Carb Friendly: It fits perfectly into your healthy eating plan, keeping those carbs way down.
- Perfect for Busy Nights: From start to finish, it’s quick enough for any weeknight.
- Amazing for Meal Prep: This casserole tastes even better the next day, making lunches a breeze!
Ingredients for Your Low Carb Philly Cheesesteak Casserole
Okay, let’s talk about what you’ll need to make this magical casserole happen! It’s pretty straightforward, but having the right stuff is half the battle, right?
For the Casserole Base:
- 1.5 pounds sirloin steak, sliced into thin strips (get the freshest you can find!)
- 1 teaspoon steak seasoning (McCormick’s Montreal Steak is my jam, but use your favorite!)
- Salt and pepper, just to your taste
- 1 cup sliced green peppers (these give it that classic Philly kick!)
- 1 cup sliced mushrooms (cremini or white button work great)
- 1 cup chopped onion (yellow or white are fine)
- 2 garlic cloves, chopped (because garlic makes everything better!)
- 2 ounces cream cheese (don’t skip this, it makes it SO creamy!)
- 1 teaspoon Worcestershire sauce (adds a little umami depth)
For the Topping:
- 2 eggs
- 0.5 cup heavy whipping cream (for that rich, custardy topping)
- 0.5 cup shredded Parmesan Reggiano cheese (the real deal for maximum flavor!)
- 4-5 slices provolone cheese, sliced into small pieces (this is key for that cheesy pull!)
Equipment You’ll Need
Alright, let’s get our kitchen arsenal ready! For this delicious Low Carb Philly Cheesesteak Casserole, you won’t need a ton of fancy gadgets, but a few key players make life SO much easier.
- A good oven-safe skillet for searing that steak and sautéing our veggies.
- A trusty 9×13 inch baking dish (or something similar, like an 8×11 or 9×9, works too!).
- A simple medium bowl for whipping up that dreamy topping.
- And if you’re planning ahead (which you totally should!), some meal prep containers are your best friend.
Step-by-Step Instructions for the Best Low Carb Philly Cheesesteak Casserole
Alright, let’s get baking! This part is where the magic really happens. Don’t worry, it’s way easier than it looks and before you know it, you’ll have a bubbling pan of cheesy goodness ready to go.
Preheating and Preparing the Steak
First things first, let’s get that oven fired up to 350°F (175°C). While it’s heating, grab your skillet – medium-high heat is the sweet spot. Toss in your thinly sliced sirloin steak. Sprinkle it generously with your favorite steak seasoning, and a pinch of salt and pepper. Give it a good sear, just for about 2-3 minutes per side, until it’s nicely browned but still a little pink inside. We don’t want to overcook it yet!
Sautéing the Vegetables and Finishing the Base
Now, let’s add those beautiful veggies right into the same skillet with the steak: the sliced green peppers, mushrooms, chopped onion, and minced garlic. Cook them all down until they’re nice and tender, and that steak is no longer pink. This is where the real Philly flavor starts to build! Now, for a super important step that I learned the hard way—drain off any extra fat. Trust me, this stops your casserole from getting watery. Then, stir in the cream cheese and Worcestershire sauce. Keep stirring until that cream cheese is all melty and creamy, coating everything beautifully. Remove the skillet from the heat.
Assembling and Baking Your Low Carb Philly Cheesesteak Casserole
In a separate medium bowl, whisk together your eggs, heavy whipping cream, and that delicious shredded Parmesan Reggiano cheese. It’ll look nice and smooth. Now, grab your baking dish and give it a quick spray with cooking spray. Pour that glorious steak and veggie mixture evenly into the dish. Drizzle that creamy egg and cheese mixture all over the top. Finally, tuck those little pieces of provolone cheese on top – they’ll melt into gooey perfection. Pop it into the preheated oven and bake for about 15-20 minutes, or until it’s bubbly and golden. Letting it cool for just a bit before serving is key! This dish gets even better when you prep it ahead, which you can learn more about here.
Tips for the Perfect Low Carb Philly Cheesesteak Casserole
Alright, let’s talk about making this Low Carb Philly Cheesesteak Casserole truly sing! It’s already pretty foolproof, but a few little tricks can take it from great to absolutely *wow*. First off, the steak! Use sirloin if you can; it’s tender and cooks up beautifully thin. If you slice it yourself, pop it in the freezer for 15-20 minutes first – makes slicing way easier, trust me! And don’t overcook the veggies; you want them tender, not mushy. Just a quick sauté is all they need. Oh, and for that cheesy perfection, good quality Provolone makes a difference, and don’t be shy with the Parmesan Reggiano! Want more pro tips for making *any* dish amazing? You gotta check out these. For another awesome take on a similar casserole, you can peek here too!
Ingredient Notes and Substitutions
Let’s dive a little deeper into some of these ingredients, because the little details really make this casserole shine! For the steak, I really love using sirloin for its tenderness, but you could absolutely get away with ribeye if you want something a bit richer. Just remember to slice it super thin! And that steak seasoning? McCormick’s Montreal Steak Seasoning is my go-to – that blend of garlic, pepper, and salt is just *chef’s kiss*. If you don’t have it, just make your own blend or use your favorite steak rub.
Now, about those veggies. Green peppers are classic Philly, but feel free to swap in red bell peppers for a touch of sweetness, or even some jalapeños if you like a little heat! And while mushrooms add an amazing earthy flavor, if they’re not your thing, just leave them out. For the cheesy goodness, the Parmesan Reggiano adds a nutty, sharp flavor that really makes the topping pop. If you can’t find it, a good quality regular grated Parmesan will still be delicious, just maybe not quite as intensely flavored. Provolone is pretty essential for that melty, stringy factor, but a good mozzarella or even a mild white cheddar would work in a pinch!
Meal Prep and Storage
This Low Carb Philly Cheesesteak Casserole is honestly a meal prep dream! You can totally whip it up a day or two ahead of time, and it’s often even tastier the next day when all those flavors have had a chance to really meld. Just let it cool completely after baking, then cover it tightly with plastic wrap or transfer it to an airtight container. Stash it in the fridge for up to 3-4 days. When you’re ready to reheat, just pop a serving in the microwave until it’s warmed through, or cover it loosely with foil and pop it in a 350°F oven for about 15-20 minutes. Easy peasy! For more genius make-ahead tips, check out this guide!
Frequently Asked Questions
Can I make this Low Carb Philly Cheesesteak Casserole ahead of time?
Oh absolutely! This casserole is fantastic for meal prep because the flavors get even better after sitting for a day. Just bake it as directed, let it cool completely, and then store it covered in the fridge for up to 3 days. When you’re ready to eat, just reheat a portion until warm.
What kind of steak is best for this casserole?
For the best tender bite, I really recommend using sirloin steak sliced thinly. You could also use ribeye for a richer flavor, but make sure to slice it super thin against the grain so it cooks up nice and tender. Freezing the steak for about 15-20 minutes before slicing really helps make this super easy!
Can I substitute the vegetables?
You sure can! While green peppers, onions, and mushrooms are classic, feel free to mix it up. Red bell peppers add a nice sweetness, and a little chopped jalapeño can give it a kick if you like things spicy. Just make sure you chop them to about the same size as the onion.
How do I make sure my casserole isn’t watery?
That’s a great question! The key is to drain off any excess fat from the skillet after you cook the steak and veggies. That way, you’re not adding extra liquid to the casserole base, which keeps it nice and creamy instead of soupy. It makes a huge difference!
Nutritional Information
Just a friendly reminder that these numbers are estimates, okay? The exact calories, carbs, protein, and fat can totally change depending on the brands you use and how strictly you follow the measurements. But based on my calculations, each serving of this delicious Low Carb Philly Cheesesteak Casserole is approximately:
- Calories: 387
- Carbohydrates: 5g
- Protein: 36g
- Fat: 24g
Pretty awesome for something so satisfying, right?

Low Carb Philly Cheesesteak Casserole
Ingredients
Equipment
Method
- Preheat your oven to 350 degrees F (175 degrees C).
- Add the sirloin steak to a skillet over medium-high heat. Season the steak with steak seasoning, salt, and pepper. Cook for 2-3 minutes, flipping both sides of the steak.
- Add the green peppers, onion, garlic, and mushrooms to the skillet. Cook until the vegetables are soft and the meat is no longer pink.
- Drain any excess fat from the skillet. This step is important to prevent a soupy casserole.
- Add the Worcestershire sauce and cream cheese to the skillet. Cook until the cream cheese has melted.
- Remove the skillet from heat.
- In a medium bowl, combine the eggs, shredded parmesan reggiano cheese, and heavy cream.
- Spray an 8×11 or 9×9 inch baking dish with oil or cooking spray. Pour the steak and vegetable mixture into the dish.
- Drizzle the egg and cheese mixture over the steak mixture. Top with the provolone cheese slices.
- Bake for 15-20 minutes, or until the cheese begins to bubble. The casserole should be ready around 18 minutes.
- Let the casserole cool before serving.
Nutrition
Notes
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Ryan Cooper, Efficiency & Testing Coordinator
I’ve spent the past six years obsessed with making cooking easier, leading to my role as Efficiency & Testing Coordinator at Low Carb Recipe Journal. My food science and ingredient analysis background helps me create low-carb recipes that actually work in real kitchens—without fancy equipment or chef-level skills.
My journey started at Mountain View Culinary Institute in kitchen operations, where I became fascinated by why some recipes fail and others succeed. I discovered my talent for spotting unnecessarily complicated cooking processes and simplifying them without losing quality. Working with restaurant chains and meal delivery services, I helped cut preparation times by 35% while maintaining delicious results.
I’ve shared my systematic approach with culinary schools and food science programs, developing testing methods now used by several meal prep companies. My “precision without perfection” philosophy drives me—amazing results shouldn’t require professional training or expensive gadgets.
This mindset stems from my love of competitive cooking and ultralight backpacking, where every step must count and simplicity is everything. I apply these same principles when testing recipes, ensuring success with standard home kitchen tools.
When I’m not testing endless recipe variations in my Denver kitchen, I’m hiking Colorado’s trails, building custom kitchen storage solutions in my woodworking shop, or spending time with my three rescue cats—Sage, Basil, and Pepper.
At Low Carb Recipe Journal, I ensure every published recipe has been thoroughly tested for reliability and ease. My goal is simple: turn complex nutritional goals into achievable daily wins that build your confidence in the kitchen.



