Cheesy Low Carb Philly Cheesesteak Casserole Recipe

I’m sharing a Low Carb Philly Cheese Steak casserole built with thinly sliced flank steak, cream cheese, provolone, mozzarella, sautéed onions and bell peppers. Garlic, heavy cream and Worcestershire sauce bind everything into a rich, high protein keto steak dinner that’s ideal for simple weeknight cooking and easy meal prep.

I love turning Philly cheesesteak into a Low Carb, High Protein casserole that actually makes weeknights way easier. I slice flank or sirloin steak thin, sear it up with a large yellow onion, green and red bell peppers and minced garlic, then stir it into a rich mix of softened cream cheese, heavy cream and a few beaten eggs.

I throw in shredded provolone and mozzarella so every bite is melty, add a splash of Worcestershire sauce, salt, black pepper and garlic powder for punch, and it bakes up golden and bubbly. Sometimes I sprinkle chopped parsley or chives on top, sometimes I don’t, either way it’s great for Keto meal prep and fits Gf Dinner Ideas when you want something satisfying without the carbs.

It feels like cheating but it’s real food, easy to make, and it keeps well so you can eat it all week, which honestly is my favorite part.

Why I Like this Recipe

1. I love the melty cheese with the chewy steak, its exactly the comfort food I want without the bread.
2. I like that its low carb so I can eat a bigger portion and still feel good about it.
3. I like that the recipe is forgiving, the tips make it hard to screw up and leftovers are great for lunches.
4. I like the way the peppers and onions caramelize, they add a sweet counterpoint to the savory meat and cheeses.

Ingredients

• Flank or sirloin steak: High in protein, low carbs, filling and savory, can be fatty.
• Yellow onion: Adds sweetness and bite, some fiber, small carb boost, very flavorful.
• Green and red peppers: Crunchy, vitamin C rich, low calorie, add sweet peppery notes.
• Cream cheese: Adds creaminess and fat, low carbs, makes casserole rich and smooth.
• Eggs: Big protein punch, helps binder the dish, adds structure and extra richness.
• Provolone cheese: Melty, adds salty tang, mostly fat and protein, very indulgent.
• Heavy cream: Very high in fat, makes it silky, adds calories but delicious.

Ingredient Quantities

• • 1 1/2 lb (680 g) flank or sirloin steak thinly sliced

• • 2 tbsp olive oil or butter

• • 1 large yellow onion thinly sliced

• • 1 green bell pepper thinly sliced

• • 1 red bell pepper thinly sliced optional but I like it

• • 3 cloves garlic minced

• • 8 oz (226 g) cream cheese softened

• • 1/2 cup (120 ml) heavy cream

• • 4 large eggs

• • 2 cups (about 8 oz / 225 g) shredded provolone

• • 1 cup (about 4 oz / 115 g) shredded mozzarella

• • 1/2 cup (about 50 g) grated Parmesan optional

• • 1 tsp Worcestershire sauce

• • 1 tsp salt

• • 1/2 tsp black pepper

• • 1/2 tsp garlic powder

• • 1/2 tsp onion powder

• • 1 tsp dried oregano or Italian seasoning

• • Nonstick cooking spray or 1 tbsp butter for greasing the dish

• • Fresh parsley or chives for garnish optional

How to Make this

1. Preheat oven to 350 F 175 C and grease a 9 by 13 inch baking dish with nonstick spray or 1 tablespoon butter. While the oven warms, pat the steak dry and slice it thinly against the grain for tenderness, then set aside.

2. Heat 2 tablespoons olive oil or butter in a large skillet over medium high heat until shimmering. Add the sliced steak in a single layer, season with 1 teaspoon salt and 1/2 teaspoon black pepper, and sear quickly about 1 to 2 minutes per side until just browned. Remove steak to a plate, it will finish cooking in the oven so dont overcook.

3. In the same skillet add a little more oil or butter if needed and toss in the thinly sliced large yellow onion and the green bell pepper and red bell pepper if using. Cook over medium heat until softened and slightly caramelized about 6 to 8 minutes. Add the minced garlic the last 30 seconds to wake up the flavors then turn off the heat.

4. Soften the 8 ounces cream cheese in a bowl, warm the 1/2 cup heavy cream slightly in the microwave for 10 seconds so it mixes smoother, then whisk in 4 large eggs until homogenous. Stir in 1 teaspoon Worcestershire sauce 1/2 teaspoon garlic powder 1/2 teaspoon onion powder and 1 teaspoon dried oregano. Taste and adjust salt or pepper if needed.

5. Fold about 1 3/4 cups of the shredded provolone and most of the shredded mozzarella into the cream cheese mixture, reserving about 1/4 to 1/2 cup of each cheese for the top. If using Parmesan, stir about 1/4 cup in now and save a little for sprinkling.

6. Layer the cooked steak evenly in the greased baking dish, then spread the sautéed onions and peppers over the steak. Pour the creamy cheese and egg mixture evenly over the meat and veggies so it fills the nooks.

7. Sprinkle the reserved provolone mozzarella and remaining Parmesan over the top. Tip: if the top looks like it might brown too fast cover loosely with foil for the first 20 minutes then remove the foil near the end so the cheese gets bubbly.

8. Bake in the preheated oven for 25 to 30 minutes until the center is set and a toothpick comes out mostly clean with a few moist crumbs. If you like a golden top, put under the broiler for 1 to 2 minutes watching closely so it does not burn.

9. Let the casserole rest 5 to 10 minutes before slicing so it firms up. Garnish with chopped fresh parsley or chives if you want, then serve. Leftovers reheat well and make great meal prep.

Equipment Needed

1. Oven (set to 350 F 175 C)
2. 9 by 13 inch baking dish, greased
3. Large skillet 10 to 12 inch, heavy bottom like cast iron or stainless
4. Cutting board
5. Sharp chef’s knife
6. Paper towels for patting steak dry
7. Tongs for searing and handling steak
8. Wooden spoon or heatproof spatula for sautéing veggies
9. Medium mixing bowl to soften cream cheese and whisk eggs
10. Whisk
11. Measuring cups and measuring spoons
12. Microwave safe bowl or small saucepan to warm the heavy cream
13. Rubber spatula for folding cheeses and scraping the bowl
14. Plate for resting the seared steak
15. Box grater for fresh Parmesan if using
16. Aluminum foil to tent the casserole if needed
17. Oven mitts or potholders
18. Toothpick or cake tester to check doneness

FAQ

Cheesy Low Carb Philly Cheesesteak Casserole Recipe Substitutions and Variations

• Steak (flank or sirloin): swap for ribeye if you want more fat and flavor, skirt steak for a stronger beefy bite, or thin-cut top round / deli roast beef if you’re short on time or cash
• Cream cheese: mascarpone gives a silkier, richer finish, ricotta mixed with a little butter mimics the texture, or full-fat Greek yogurt (strained) if you want less fat
• Heavy cream: use half and half plus 1 tbsp melted butter per cup to bump fat, whole milk thickened with 1 tbsp cornstarch per cup, or coconut cream for a dairy-free option
• Eggs: 2 tbsp plain yogurt or sour cream can replace one egg as a binder in rich casseroles, 1/4 cup silken tofu blended per egg works for vegan swaps, or use a commercial egg replacer per package directions
• Provolone / mozzarella: fontina or young gouda melt similarly and add nice flavor, mild cheddar gives a sharper profile, Monterey Jack melts well and keeps the dish mild

Pro Tips

1. Chill the steak for about 20 to 30 minutes before slicing so it firms up and you can get super thin slices, slice against the grain or it will be tough. Pat the pieces dry right before searing so you get a good quick browning and not a soggy pan.

2. Dont rush the peppers and onions, cook them longer than you think until they’re nicely browned and a lot of the water has cooked off, or salt them, let sit for a few minutes and squeeze out excess moisture. That little extra time stops the casserole from turning watery.

3. For a silky, lump free cheese custard whisk the eggs first, then slowly temper them with the warmed cream before mixing into the cream cheese. Or better yet throw the whole mix in a blender for 10 seconds it will be totally smooth and save you the elbow grease.

4. Let the finished bake rest at least 10 to 15 minutes before cutting so it firms up, use a hot sharp knife wiped clean between slices for neat pieces, and if you want a perfectly browned top cover loosely for the first 20 minutes then uncover and broil very briefly while watching it so it does not burn. Also an instant read thermometer around 160 degrees Fahrenheit helps you know it’s set without overcooking.