Boil the cavatappi in well-salted water until 2 minutes underdone (about 7 to 8 minutes), then drain without rinsing and set aside.

In the same pot over medium heat, melt the butter, add the flour, and stir for 90 seconds until the roux is pale and smells faintly nutty.

Whisk in the whole milk gradually, then add the heavy cream, and stir over medium heat for 4 to 5 minutes until the sauce coats the back of a spoon.

Stir in the dry mustard powder, garlic powder, onion powder, kosher salt, black pepper, smoked paprika, and hot sauce if using, and cook for 30 seconds.

Reduce heat to low and add the sharp cheddar and mild cheddar one handful at a time, stirring after each addition until fully melted, about 3 minutes total.

Fold in the drained cavatappi over low heat for 2 to 3 minutes, then spoon into a warm serving bowl and finish with a pinch of smoked paprika and freshly ground black pepper.