Make the sauce: To the pan with the onions and garlic add butter and cook over low heat until melted. Next, add the pumpkin puree, heavy whipping cream, chicken broth, Italian seasoning, and salt and pepper. Then, stir altogether until ingredients are combined. Simmer over low heat for three minutes. The sauce should be creamy and not too thin, so it can coat all the noodles. Then, add the noodles to the sauce and stir gently to combine. Finally, top with parmesan cheese.