Step 1

Bring a large pot of salted water to a boil. Add 12 ounces pipette rigate or medium shells pasta and cook until al dente according to package instructions. Meanwhile, grate 8 ounces white cheddar cheese on the large holes of a box grater (about 2 cups). Tear or chop 8 slices white American cheese into small pieces (1 cup).

Step 2

When the pasta is ready, drain.

Step 3

Melt 4 tablespoons unsalted butter in a large saucepan over medium-high heat. Add 1/4 cup all-purpose flour and cook, stirring constantly, until lightly toasted, about 1 minute. Add 1 teaspoon kosher salt, 1/2 teaspoon ground dry mustard, and 1/4 teaspoon hot sauce, and stir to combine. While whisking constantly, slowly pour in 3 cups whole milk and 1/2 cup heavy cream. Bring to a boil, about 5 minutes. Boil, stirring frequently, until thick enough to coat the back of a spoon, 4 to 6 minutes.

Step 4

Reduce the heat to low. Add the white cheddar cheese and American cheese one handful at a time, stirring until each handful is melted before adding the next. Add the pasta and stir to combine. Taste and season with more kosher salt as needed.