16 ounces small pasta (I used elbows but shells work great too)
1/4 cup unsalted butter
1/2 cup all-purpose flour
2 1/2 cups milk (either 2%, whole milk, or heavy cream)
6 slices white American cheese, chopped into pieces
1 cup shredded extra sharp white cheddar
1 tablespoon Dijon mustard (use less or more depending on taste preferences)
1 teaspoon kosher salt
1/4 teaspoon hot sauce
Cook pasta according to package directions; drain.
Meanwhile, melt the butter in a medium sauce pan over medium-low heat heat until melted. Whisk in the flour; cook for 1 minute, whisking constantly. Gradually whisk in the milk until smooth. Cook until sauce thickens and bubbles, whisking frequently, about 5-10 minutes. Remove sauce pan from the heat.
Gradually add in the cheeses,stirring as you add, followed by the mustard, salt, and hot sauce. Stir until mixture is smooth and cheese has completely melted. If necessary, return mixture to heat to allow sauce to melt.
Stir in the pasta and cook over medium heat for one additional minute or until completely heated through.