No-Bake Crispy Potato Chip Mac and Cheese

Ingredients (9)

• + 1 cup elbow macaroni, uncooked add to pantry
• + 1 (8 ounce) bag white cheddar kettle-style potato chips, crushed into medium-fine crumbs add to pantry
• + ⅓ cup finely grated Parmigiano-Reggiano add to pantry
• + 2 tablespoons plain dry bread crumbs add to pantry
• + 1 tablespoon butter add to pantry
• + 4 cups prepared white sauce (see footnote) add to pantry
• ✓ ½ pound shredded extra-sharp Cheddar cheese
• + ¼ pound shredded Gruyere cheese add to pantry
• + ¼ teaspoon dry mustard add to pantry