Buffalo Spaghetti And Meatballs

Name: Buffalo Spaghetti And Meatballs
Ingredients: 1 stick unsalted butter; 1 large onion, finely chopped; Kosher salt; 2 28-ounce cans whole peeled San Marzano tomatoes, crushed; 1 1/2 teaspoons dried oregano; 2 fresh bay leaves; Freshly ground pepper; 1 1/2 pounds ground beef; 3/4 cup grated Parmesan cheese, plus more for topping; 1/2 cup shredded carrots; 1/2 cup minced celery, plus celery leaves for topping; 1/3 cup breadcrumbs; 3 scallions, thinly sliced; 2 large eggs; 1/4 cup milk; 1/2 cup plus 2 tablespoons hot sauce (such as Frank’s), plus more for serving; 1/4 cup heavy cream; 1 pound spaghetti; Crumbled blue cheese, for topping