In a mixing bowl, whisk together the cream cheese and heavy cream and blend until smooth
Cook the pasta in plenty of boiling salted water until al dente. Drain well. Pour the hot pasta into the bowl with the cream cheese and cream. Add the green onions, crawfish tails, Fontina, Gruyere, salt and pepper and mix until well blended.
In a small mixing bowl, blend the Panko, Parmigiano, truffle oil, and creole seasoning.
Divide the pasta into individual casseroles. Top with equal amounts of the bread crumb mixture. Bake until hot and the topping in crisp.