Place a large pot of water over high heat and bring to a boil
While the water is heating, shred the 8 ounces of white cheddar and set aside for now
As soon as the water begins to boil, add a generous pinch of salt and cook the pasta according to manufacturer’s directions
While the pasta is boiling, place a pot over medium heat and add 4 tablespoons of butter
Once the butter has melted, whisk in 1/4 cup of all purpose flour and cook while whisking for about 60 seconds
Whisk in 1 1/2 cups of whole milk and 1 cup of heavy cream and season with a teaspoon of salt, 1/4 teaspoon of black pepper and the optional dijon mustard and hot sauce
Continue whisking until the mixture begins to simmer
As soon as it begins to simmer, reduce the heat to low and slowly add the shredded sharp cheddar and 15 ounces of ricotta stirring as you go
As soon as the cheese has all been added and has fully melted, drain the cooked pasta and transfer it into the cheese sauce
Mix until the pasta is fully incorporated and transfer into the prepared baking dish