Vegetarian Italian Baked Ziti

1 . Stage

Heat olive oil in a 12-inch skillet over medium-high heat. Add mushrooms, onion, bell pepper, celery, and garlic; saute until tender, 5 to 7 minutes. Stir in spaghetti sauce, tomatoes, parsley, 1 teaspoon oregano, and basil. Cover, reduce heat, and simmer for 2 hours.

2 . Stage

Preheat the oven to 350 degrees F (175 degrees C). Oil a 9x13-inch baking pan.

3 . Stage

Just before the sauce is finished, bring a large pot of lightly salted water to a boil. Add ziti and cook, stirring occasionally, until tender yet firm to the bite, about 11 minutes. Drain.

4 . Stage

Combine cottage cheese, mozzarella cheese, 1/2 of the Parmesan substitute, egg, salt, and pepper in a bowl. Mix remaining Parmesan substitute and 1/2 teaspoon oregano in another small bowl.

5 . Stage

Spread 1 cup sauce in the bottom of the prepared pan. Layer 1/3 cup ziti, 1 cup sauce, and 1/3 cottage cheese mixture; repeat layers twice more. Top with any remaining sauce, then sprinkle with oregano-Parmesan blend.

6 . Stage

Cover with foil and bake in the preheated oven until bubbly, about 1 hour.