Preheat your oven to 375°F (190°C). Lightly grease a 9x13 inch baking dish.

In a large skillet over medium-high heat, cook the ground Italian sausage (or ground beef), breaking it apart with a spoon, until fully browned. If using ground beef, drain any excess fat. Add the diced yellow onion and bell pepper to the skillet and cook for 5-7 minutes until softened. Stir in the minced garlic and cook for another minute until fragrant.

Stir in the dried oregano, dried basil, marinara sauce, salt, and black pepper. Bring the mixture to a simmer, then reduce heat to low and let it gently simmer for 5 minutes, allowing the flavors to meld.

While the sauce simmers, in a medium mixing bowl, combine the ricotta cheese, 1/2 cup grated Parmesan cheese, egg, chopped fresh parsley (if using), 1/4 tsp salt, and 1/8 tsp black pepper. Mix until well combined.

Spread the entire meat sauce mixture evenly into the prepared 9x13 inch baking dish. Drop spoonfuls of the ricotta cheese mixture over the meat sauce, then gently spread it out, leaving some of the meat sauce exposed. Sprinkle 1 cup of shredded mozzarella cheese over the ricotta layer.

Unroll the two cans of crescent roll dough. Carefully place the triangles over the top of the cheese layer, arranging them to form a solid crust. Pinch seams together to seal any gaps.

In a small bowl, whisk together the melted butter and garlic powder. Brush this mixture evenly over the crescent roll dough. Sprinkle the remaining 1 cup of shredded mozzarella cheese and the 2 tablespoons of grated Parmesan cheese over the top.

Bake for 30-35 minutes, or until the crescent roll topping is golden brown and puffed, and the casserole is bubbly around the edges. If the crescent topping is browning too quickly, you can loosely tent it with foil.

Remove the casserole from the oven and let it rest for 5-10 minutes before slicing and serving. This helps the layers set and makes it easier to serve.