Preheat the oven to 350°F (175°C).

Cook the ground beef: Heat a large skillet over medium heat and add the olive oil. When the pan is heated, incorporate the ground beef, using a spatula to crumble it as it cooks. Cook for about 8–10 minutes until browned. Season with salt and pepper, then drain any excess fat and set the beef aside.

Sauté the veggies: In the same skillet, add the sliced bell peppers and chopped onion. Sauté for approximately 5 to 7 minutes, stirring from time to time, until it becomes tender.

Season the mixture: Add the smoked paprika, Italian seasoning, and garlic powder to the peppers and onions. Stir to combine and cook for an additional 1–2 minutes to allow the spices to blend.

Combine the casserole base: In a large mixing bowl, combine the cooked ground beef with the sautéed vegetables. Stir in the cream cheese until it melts and evenly coats the beef and veggies.

Assemble the casserole: Transfer the beef and veggie mixture to a greased 9x13-inch baking dish. Evenly distribute the Provolone cheese over the top.

Bake the casserole: Place the casserole in the preheated oven and bake for 15–20 minutes, or until the cheese is melted and bubbly.

Serve and enjoy: Remove from the oven and let the casserole rest for a few minutes before serving. Enjoy the rich, cheesy goodness of this Keto Philly Cheesesteak Casserole!