4 Tablespoons butter
1/4 cup all-purpose flour
2 1/2 cups milk anything but skim milk
4 ounces (about 6 slices) sliced white American cheese from the deli counter, cut into thin strips
8 oz extra-sharp white Vermont cheddar shredded
1/2 teaspoon Dijon mustard optional
1 teaspoon kosher salt
1/4 teaspoon hot sauce optional
Prepare pasta according to package directions. In large saucepan over low heat, melt butter. Whisk in flour and cook 1 minute, whisking constantly. Gradually whisk in milk; cook over medium heat, whisking until mixture thickens and bubbles. Remove from heat. Add cheeses, mustard, salt, and hot sauce, stirring until cheese melts and sauce is smooth. Stir in pasta and cook over medium heat for 1 minute (or until thoroughly heated). Serve immediately.