Ingredients

• 2 (1 ounce) packages dry onion soup mix
• 1 (16 ounce) package thin spaghetti, broken into halves
• 1 tablespoon butter, or to taste
• 1 cup chopped green bell pepper
• 2/3 cup coarsely chopped onion
• 3 cups quartered zucchini slices
• 1 (28 ounce) can petite diced tomatoes
• 1/4 cup parsley
• 1 teaspoon salt
• 1/8 teaspoon ground black pepper
• 1 1/4 cups shredded Swiss cheese
• 1 1/4 cups shredded mozzarella cheese

Instructions

1. Preheat oven to 350 degrees F (175 degrees C).
2. Bring a large pot of water to a boil. Stir onion soup mix into the boiling water. Cook spaghetti in the boiling water, stirring occasionally, until barely tender, 6 to 7 minutes; drain. Pour spaghetti into a casserole dish.
3. Melt butter in a large skillet over medium heat. Cook and stir bell pepper and onion in hot butter until slightly tender, about 4 minutes; add zucchini, place a cover on the skillet, reduce heat to medium-high, and cook until zucchini is soft, about 10 minutes.
4. Stir tomatoes, parsley, salt, and pepper into the vegetable mixture; replace cover and cook until the tomatoes are heated through, 3 to 5 minutes.
5. Pour the vegetable mixture over the spaghetti and mix. Spread Swiss cheese and mozzarella cheese over the vegetable and pasta mixture. Cover dish with aluminum foil.
6. Bake in preheated oven until heated in the center, about 40 minutes.