Philly Cheesesteak Casserole turns paper-thin flank steak, bell peppers, onion, and three cheeses into a rich low-carb main dish without pasta or bread. A short baking-soda marinade tenderizes the steak before fast skillet cooking and a golden provolone finish.
The recipe makes six generous servings. Preparation takes 30 minutes, cooking takes 45 minutes, and the listed total is 75 minutes. The steak marinates for 15–30 minutes, and the assembled casserole bakes at 400°F for 15 minutes.
Philly Cheesesteak Casserole Ingredients
The marinade uses 2 tablespoons each red wine vinegar and Worcestershire sauce, 1 teaspoon baking soda, 4 divided garlic cloves, ½ teaspoon each onion powder, dried thyme, and salt, ¼ teaspoon black pepper, and 2 cups water.
For the casserole, use 2 lb flank steak sliced paper-thin against the grain, 2 tablespoons divided salted butter, 1 tablespoon vegetable oil, 1 red pepper, 1 green pepper, 1 cup white onion, 4 oz cream cheese, ½ cup heavy cream, 1 cup Monterey Jack, exactly 6 provolone slices, and parsley.
If you enjoy this recipe, you may also like Chicken Bacon Ranch Casserole.
How to Make Philly Cheesesteak Casserole
- Whisk vinegar, Worcestershire, baking soda, half the garlic, onion powder, thyme, salt, pepper, and water.
- Slice steak against the grain no thicker than ⅛ inch and marinate 15–30 minutes.
- Slice vegetables, grate Monterey Jack, soften cream cheese, and heat the oven to 400°F.
- Heat 1 tablespoon butter with the oil over medium heat. Drain and discard the marinade, then brown steak in uncrowded batches and remove.
- Add remaining butter; cook peppers and onion about 5 minutes and remaining garlic 1 minute.
- Melt cream cheese and heavy cream into the vegetables, then stir in Monterey Jack.
- Return steak, transfer to a casserole dish, top with six provolone slices, and bake 15 minutes. Garnish with parsley.
Prepare the Exact Marinade
Slice Paper-Thin Against the Grain
Prepare the Vegetables, Cheese, and Oven
Brown Steak in Batches
Cook Peppers and Onion for Five Minutes
Make the Creamy Monterey Jack Sauce
Return the Steak to the Sauce
Bake Under Six Provolone Slices
Serving, Storage, and Reheating
Conclusion
Whisk the exact vinegar, Worcestershire, baking soda, garlic, seasoning, and water marinade. Slice 2 lb flank steak no thicker than ⅛ inch against the grain and soak 15–30 minutes. Drain and brown in batches. Cook peppers and onion 5 minutes and garlic 1 minute, then melt in cream cheese, heavy cream, and Monterey Jack. Return steak, top the casserole with six provolone slices, and bake at 400°F for 15 minutes.
Frequently Asked Questions
- → How long should I marinate the flank steak?
Marinate the paper-thin slices for 15–30 minutes, then drain and discard the liquid.
- → Why is baking soda used in the marinade?
It tenderizes the thin flank steak during the short soak, helping it stay tender through browning.
- → Does Philly Cheesesteak Casserole contain pasta?
No. This casserole contains steak, peppers, onion, and cheeses and is listed as low-carb.
- → What temperature and time should I bake it?
Top with exactly six provolone slices and bake at 400°F for 15 minutes.