Italian Wedding Casserole

Name: Italian Wedding Casserole
Ingredients: 1 pound bowtie pasta; 2 tablespoons salted butter; 2 tablespoons olive oil; 1 cup diced celery; 2 tablespoons chopped fresh oregano; 3 cloves garlic, minced; 2 carrots, diced; 1 onion, diced; 3 tablespoons all-purpose flour; 4 cups chicken stock; Kosher salt and freshly ground black pepper; One 26-ounce bag frozen Italian meatballs; 4 cups chopped kale; 1/2 cup grated Parmesan or asiago; 1 1/2 cups breadcrumbs; 1/4 cup grated Parmesan; 3 tablespoons salted butter, melted; 2 tablespoons chopped fresh parsley