Prep the vegetables and gather the ingredients. Get out a 13x9 baking dish. Preheat the oven to 350 degrees F.

Pour the tomato sauce into a pot or large saucepan. Add the vegetables and cook over medium-low heat for about 20 minutes, stirring frequently, until the veggies are softened to your liking. Remove from heat.

In the meantime, boil a pot of salted water. Cook the ziti about 2 to 3 minutes less than the package suggests. Drain and rinse the ziti.

In a large bowl, mix together all of the ricotta, 1 cup of the mozzarella, ½ cup of the parmesan, and the beaten egg.

Put the cooked ziti in the bowl and stir well to coat it in the cheese mixture.

Pour half of the sauce into the bottom of the baking dish. Spoon the ziti and cheese mixture on top. Pour the rest of the sauce on top. Sprinkle the rest of the mozzarella and parmesan cheese on top.

Cover the dish with foil. Bake for 25 to 30 minutes, remove the foil, and bake for another 5 to 10 minutes or until the cheese is bubbling.

Remove from the oven and let it sit for about 5 to 10 minutes. Garnish with the chopped parsley before serving.