Step 1

Preheat the oven to 375F. Cook the pasta according to package directions. Drain and set aside in a large baking dish.

Step 2

Meanwhile, place half of the mushrooms in a food processor and pulse a few times, just until small chopped. Repeat with the remaining mushrooms.

Step 3

Heat the oil in a large deep pan over medium-high heat. Add the mushrooms and cook stirring occasionally, for 8-10 minutes.

Step 4

Once the mushrooms reduced their size to about a half of the amount, stir in the oregano, paprika, onion and garlic. Continue to cook for 5-6 minutes, stirring frequently. Stir in the marinara sauce and simmer for a couple of minutes. Season the sauce with salt and pepper.

Step 5

Pour the sauce over the cooked spaghetti and gently stir to combine; sprinkle with the mozzarella and parmesan. Bake the casserole for 25-30 minutes, or until bubbly and the cheese is melted.

Step 6

Garnish with freshly chopped parsley, if desired, and serve warm.