Preheat the oven to 350 degrees F.
Cook the spaghetti according to package directions.
While you are waiting for the water to boil and spaghetti to boil, cook the vegetables.
In a large skillet, add the olive oil over medium-high heat.
Add the onion, red bell pepper, and zucchini. Season with
Cook until the vegetables are softened, about 7-10 minutes, stirring occasionally.
Add the garlic and 1 teaspoon Italian seasoning, and cook another minute.
Add the pasta sauce, stirring to combine. Remove from heat.
In a medium bowl, combine the cottage cheese, cream cheese, 1 cup of Italian cheese, and remaining 1 teaspoon Italian seasoning. Mix well to combine.
Spray a 9x13" baking dish with cooking spray.
Add ½ of the spaghetti to the bottom of the dish.
Top with the cottage cheese mixture, spreading it out evenly on top of the spaghetti noodles.
Top with remaining noodles.
Top the noodles with the thin slices of butter, spacing them out evenly.
Pour the vegetable marinara on top of the butter and noodles evenly.
Finally, top with the remaining 2 cups of cheese.
Bake in the preheated oven for 35-40 minutes, until the top is golden brown.
Let cool for about 5 minutes.
Serve topped with fresh parsley, and enjoy!