In two cup increments, start to stir in your cheese. Don’t add more cheese until the prior cheese has made your sauce silky smooth. Once you’ve finished mixing in cheese the sauce should be smooth and creamy
Pour your finished pasta into the cheese sauce and mix well. You want all the pasta to get sauce on it
In a 9 x13 baking dish pour half the pasta/sauce mixture into the pan. Take 2 cups of the topping cheese and spread over pasta/sauce mixture. Pour the rest of the pasta/sauce mixture over the top and finish with the remaining 2 cups of cheese left
Place in the oven for 30 minutes or until the top is golden brown. Serve immediately or refrigerate for later.