Boil the pasta JUST until al dente, according to package directions. Drain and return to the pan you boiled it in. Set aside. (Mix in a little butter to keep the noodles from sticking if it's going to be awhile before you make the sauce)

Preheat the oven to 375 degrees Fahrenheit.

To a medium saucepan over medium heat, add the butter. When the butter has melted, add the flour, salt, dry mustard, pepper, and 1/8 teaspoon smoked paprika. With a wooden spoon or whisk, stir constantly for three minutes.

Add the milk in a thin stream, stirring constantly with a whisk. Continue to stir constantly until the sauce thickens enough to coat the back of a spoon, 5-8 minutes.

Remove from heat and add 2 cups of the cheese, stirring until melted. You'll reserve the last cup of cheese for topping. Pour the cheese sauce over the pasta and toss gently until all of the pasta is coated.

Add half the pasta to a two-quart casserole dish (I like a tall 8-inch by 8-inch baking dish). Sprinkle on half the cheese. Add the rest of the pasta. Sprinkle on the rest of the cheese, then dust lightly with the smoked paprika.

Bake for 25-30 minutes, until the mac and cheese is bubbling and browning on top.

Serve, topping individual servings with parsley or cooked, chopped bacon if desired.