Bring a large pot of salted water to a boil. Add the pasta and cook for a minute less than al dente. The pasta will finish cooking in the oven.
Heat a saucepan or pot over medium heat. Add the butter. Once melted, whisk in the flour and cook for 1 minute until it starts to bubble and turns a golden yellow color.
Slowly pour in the half and half while whisking continuously until smooth. Then, add the dry mustard powder, smoked paprika, garlic powder, black pepper, nutmeg, cayenne powder if using, salt, and cream cheese. Whisk until smooth. Continue to cook the sauce for 3 to 4 minutes or until it thickens.
Reduce the heat to low or remove from heat and add the sharp cheddar, Colby jack, and smoked gouda. Whisk until there are no clumps and the sauce is smooth. Taste and adjust seasoning to your preference.
Once the pasta is cooked, drain it and immediately toss it into the sauce. Mix together in a large baking dish.
Bake at 350°F for 15 minutes. Then, turn on the broiler for a few minutes until the top is golden and crispy – keep an eye on it!
Sprinkle chopped parsley and grated parmesan on top and enjoy your delicious mac and cheese!