Cooking should be an adventure, not a chore. Let’s dive into the step-by-step process to bring this delicious pot pie to life.

1. Preheat your oven to 375°F (190°C) and grease a pie dish or oven-safe skillet.
2. In a large skillet, heat olive oil over medium heat. Add the onion and garlic, sautéing until fragrant, about 2-3 minutes.
3. Add the diced bell pepper and mushrooms, cooking until they begin to soften, approximately 5 minutes.
4. Stir in the marinara sauce, followed by the Italian seasoning, salt, and pepper. Let the mixture simmer for about 5-7 minutes, allowing the flavors to meld.
5. Remove the skillet from heat and stir in the shredded mozzarella cheese and pepperoni or sausage, if using.
6. Roll out the pie crust on a lightly floured surface and carefully place it over the filling, tucking the edges into the sides of the dish. Cut a few slits on top for steam to escape.
7. Brush the crust with the beaten egg to achieve a beautiful golden finish.
8. Bake in the preheated oven for 25-30 minutes or until the crust is golden brown and the filling is bubbly.
9. Allow the pot pie to cool for a few minutes before serving. Enjoy the comforting aromas as you slice into your warm, cheesy creation.