Potluck Italian Sausage Casserole

Ingredients

• 1 (16-ounce) box penne
• 1 pound ground Italian sausage
• 1 tablespoon butter
• 1 tablespoon olive oil
• 1 medium onion, finely chopped
• 1 medium carrot, finely chopped
• 1 1/2 teaspoons dried oregano
• 1 teaspoon salt
• 1/2 teaspoon pepper
• 1 small zucchini, halved lengthwise and sliced
• 1 cup fresh mushrooms, chopped
• 6 cloves garlic, minced
• 1 (15-ounce) can tomato sauce
• 1 (14-ounce) jar pasta sauce with meat flavoring
• 2 cups part-skim mozzarella cheese, shredded
• fresh parsley, optional, to taste, minced