Four-Cheese Truffled Macaroni and Cheese

Ingredients (10)

• + 1 (16 ounce) package cavatappi (corkscrew macaroni) add to pantry
• + 6 tablespoons butter add to pantry
• + ½ cup flour add to pantry
• + 5 ½ cups milk, divided add to pantry
• + 2 ½ cups shredded smoked Gouda cheese add to pantry
• + 2 cups shredded sharp Cheddar cheese add to pantry
• + 1 ½ cups shredded Swiss cheese add to pantry
• + 1 ½ cups grated Parmesan cheese, divided add to pantry
• + ½ cup dry bread crumbs add to pantry
• ✓ 1 tablespoon truffle oil