Cook the pasta in salted water according to the package instructions to al dente. Drain and set aside the cooked pasta. To avoid the pasta from sticking together, mix a little bit of oil, about 1 teaspoon into the pasta to coat.
In a large mixing bowl, add the freshly grated cheeses and mix to combine. Transfer 10 ounces (2 1/2 cups) of the cheese mixture into a separate bowl. That will be for the sauce. The remaining cheese will be used for layering and topping the mac n cheese.
In a large saucepan or pot under medium heat, melt the butter. Mix in the seasonings (paprika, garlic powder, onion powder, salt and ground white pepper) followed by the flour and cook while whisking continuously for 1 to 2 minutes.
Next, slowly whisk in the milk into the roux followed by the heavy cream and buffalo sauce. Cook the mixture while whisking continuously until it starts to thicken, about 3 to 5 minutes.
Turn the heat down to low. Whisk in the softened cream cheese into the sauce until it is fully incorporated.
Next, whisk in the divided 10 ounces (2 1/2 cups) of the cheese mixture into the sauce until it is fully incorporated. Remove the pan from the heat.
In the pan with the sauce, add in the chicken and pasta. Mix ingredients together to combine making sure that all of the chicken and pasta are evenly coated in the cheese sauce.
Preheat the oven to 350F. In a lightly greased large baking pan (8 x 12 or 9 x 13 inch), spoon half of the buffalo chicken mac n cheese. Sprinkle over half of the remaining cheese mixture. Repeat this process ending with the last of the cheese mixture. Cover the pan with aluminum foil.
Transfer assembled mac & cheese to the preheated oven and bake for 25 to 30 minutes. For a toasted top, remove the aluminum foil and broil the mac & cheese on for 3 to 5 minutes. (I baked the mac & cheese for 25 minutes and broiled for 4 minutes, for reference)
Let the Mac n cheese rest at room temperature for 5 to 10 minutes. Top with fresh chopped chives, optional. Serve Buffalo Mac n Cheese while warm and gooey. For an extra pop of buffalo flavor, drizzle over some extra buffalo sauce. Enjoy!