Step 1: Prepare the Beef and Vegetables

Heat 1 tablespoon olive oil in a large skillet over medium-high heat.

Add the sliced beef steak, season with salt, pepper, and oregano, and sauté for 5-7 minutes until browned and cooked through.

Remove the beef from the skillet and set it aside.

In the same skillet, add the remaining 1 tablespoon olive oil and sauté the onions, bell pepper, and minced garlic for 5 minutes, or until they soften and become caramelized. This step enhances the sweetness of the vegetables and complements the beef’s richness.

Step 2: Combine the Casserole Layers

While the beef and vegetables are cooking, in a large bowl, combine the frozen hash browns, heavy cream, beef broth, and Worcestershire sauce. Stir everything together.

Season with salt and pepper, and add the dried basil for extra flavor.

Spread the hash brown mixture evenly in the bottom of a greased 9×13-inch baking dish.

Step 3: Layer the Casserole

Evenly distribute the cooked beef over the hash brown base.

Layer the sautéed onions, peppers, and garlic on top of the beef.

Sprinkle the shredded provolone, mozzarella, and Parmesan cheese evenly over the top of the casserole. These cheeses will melt perfectly to create the creamy, cheesy top layer.

Step 4: Bake

Cover the casserole with aluminum foil and place it in the preheated oven at 375°F (190°C).

Bake for 25-30 minutes, then remove the foil and bake for an additional 10 minutes to allow the cheese to turn golden brown and bubbly.

You’ll know the casserole is done when the cheese is melted and bubbling at the edges.

Step 5: Serve

Let the casserole sit for about 5 minutes before serving to allow the layers to set.

Garnish with extra Parmesan cheese or fresh parsley for an added touch of flavor.

Slice and serve the comforting layers of this Philly cheesesteak casserole.